Silicone-containing ocular lens material with high safety and preparing method thereof

ABSTRACT

The present invention provides a safe ocular lens material having high oxygen permeability, excellent surface wettability, the excellent lubricity/easy lubricating property of surface, little in surface adhesive and superior flexibility and stress relaxation, in addition, suppressing elution of a monomer from the final product. That is, the present invention relates to an ocular lens material comprising at least one kind of a compound (A) having an ethylenically unsaturated group and polydimethylsiloxane structure through a urethane bond and at least one kind of a pyrrolidone derivative (B) in which a polymerizable group is a methylene group.

TECHNICAL FIELD

The present invention relates to an ocular lens material and a preparingmethod thereof. More specifically, the present invention relates to anocular lens material excellent in surface wettability and thelubricity/easy lubricating property of surface in addition to highoxygen permeability and flexibility which can be preferably used as acontact lens, an intraocular lens, an artificial cornea, cornea onlay,cornea inlay and the like, and a preparing method thereof.

BACKGROUND ART

1-Vinyl-2-pyrrolidone (hereinafter, referred to as N-VP) is used forpreparing industrially useful and typically water-soluble polymer.However, it has a defect that copolymerizability with an alkyl(meth)acrylate and an alkyl (meth)acrylamide which are industrially andfrequently used is low because of having a vinyl group. Consequently,when the polymerization of a material using N-VP, in particular, UVpolymerization for curing in a short time is carried out, an unreactedmonomer tends to be increased.

It is described in JP-A-58-152017 that in order to improvepolymerizability and prepare a water-soluble polymer useful for variousindustries, 1-methyl-3-methylene-2-pyrrolidone (hereinafter, referred toas 1,3-MMP) having a pyrrolidone structure is used. Also, awater-containing contact lens material comprising 1,3-MMP as a maincomponent is described in JP-B-1-15847 and JP-B-6-82177. 1,3-MMP has anamide group adjacent to a methylene group and is a compound having asimilar structure as an alkyl (meth)acrylamide which is frequently usedin the technical field to which the present invention belongs.Accordingly, 1,3-MMP has good solubility with the alkyl (meth)acrylamideand alkyl (meth)acrylate and is superior in copolymerizability. Forexample, in JP-B-6-82177, a hydrogel with high water content having awater content of 70% by weight or more in which 1,3-MMP and N-VP wascopolymerized is described. It is described in these references that ahydrogel superior in flexibility is obtained by using 1,3-MMP as a maincomponent. However, although the hydrogel with high water content issuperior in flexibility, only a contact lens inferior to keep its shapeis prepared. In addition, the oxygen permeability of the contact lenscomprising gels with high water content which are described in thesepatent references is greatly lower than the oxygen permeability ofwater, it cannot be said that it can permeate oxygen necessary for thecornea considering the wearing state at continuous wearing or at shortsleep.

On the other hand, many silicone hydrogel materials which used ahydrophobic silicone compound as a main component have been recentlyreported in order to improve oxygen permeability of a lens to thecornea. Further, since silicone compounds are used, the wettability ofmaterial surface is poor, and it is described in U.S. Pat. No. 5,486,579specification in order to improve the wettability that N-VP which is astrongly hydrophilic monomer is copolymerized. However, as describedabove, since N-VP is low in copolymerizability with (meth)acrylate,there is high possibility that N-VP remains as an unreacted monomer in aproduct material when the copolymer is used as a medical device.Further, many works are required for providing a safe medical devicehaving no residue. Consequently, in order to improve the problem, thestructure of a monomer for unionizing the polymerizable group of otherpolymerizable components is designed in U.S. Pat. No. 5,486,579specification for improving copolymerizability with N-VP. However, it isrequired to carry out the monomer design and production of allpolymerizable components for using components having various functions.This is very difficult in any traders.

Further, a contact lens comprising 1,3-MMP and a silicone-containing(meth)acrylate and/or a fluoroalkyl (meth)acrylate is described inJP-A-6-214197. In the patent, the copolymerization of thesilicone-containing (meth)acrylate and/or a fluoroalkyl (meth)acrylatewhich is used for an oxygen permeating contact lens material isdescribed in order to improve rigidity to keep its shape and mechanicalstrength. However, the contact lens material being a target has a watercontent of about 37 to 58% and an oxygen permeation coefficient of about26 to 35 and it cannot be said that it has adequate oxygen permeabilityconsidering the wearing state at continuous wearing or at short sleep.Further, the copolymer of the silicone-containing (meth)acrylate and/ora fluoroalkyl (meth)acrylate and a hydrophilic monomer as a maincomponent described in JP-A-6-214197 is insufficient in the shapestability and mechanical strength.

The solubility of components composing the material is important inproduction of a hydrogel containing silicone. Since a materialcomprising a silicone-containing monomer and a strongly hydrophilicmonomer tends to cause phase separation in the material, it is difficultto obtain a transparent material. An organic solvent is often used inpolymerization in such a system poor in solubility. For example, apreparing method of a contact lens using 5 to 60% by weight of anorganic solvent is shown in Japanese Patent No. 3249123 and a method ofevaporating the solvent at a specific temperature to remove it is shownin the fore-mentioned preparing method of Japanese Patent ApplicationNational Publication (Laid-Open) No. 8-503173. However, the amount ofthe organic solvent used is much as several tens % in these referencesand when an adequate amount of organic solvent is used for obtaining atransparent material, the degree of polymerization tends to be lowbecause of radical chain transfer to the organic solvent; therefore thelowering of the strength of a material itself cannot be evaded. Further,for the same reason, the elution amount of a monomer and an oligomerfrom a material is much. Further, it is troublesome and difficult toremove a large amount of the organic solvent from the system and themethod is not suitable considering mass production.

The present invention was achieved considering the fore-mentionedconventional techniques and it is the purpose of the present inventionto provide an ocular lens material excellent in oxygen permeability,surface wettability and the lubricity/easy lubricating property ofsurface, little in surface adhesive and having superior flexibility andrepulsive property, and a preparing method thereof. Further, it is thepurpose of the present invention to provide a safe ocular lens materialby improving low polymerizability which is observed in a system usingN-VP as a hydrophilic component, establishing a system in which aresidual component can be reduced in production of a lens, andsuppressing a monomer eluted product from the final product.

DISCLOSURE OF INVENTION

As a result of extensively studying to obtain the ocular lens materialhaving the fore-mentioned properties, the present inventors have foundthat the ocular lens material in which a compound having ethylenicallyunsaturated groups and polydimethylsiloxane structures through aspecific urethane bond and a pyrrolidone derivative represented by1,3-MMP in which a polymerizable group is a methylene group, forexample, 1-alkyl-3-methylene-2-pyrrolidone,1-alkyl-5-methylene-2-pyrrolidone, and 5-alkyl-3-methylene-2-pyrrolidoneare essential components has the fore-mentioned properties incombination and have completed the present invention.

Namely, the present invention relates to an ocular lens materialcontaining (A) at least one kind of a compound having ethylenicallyunsaturated groups and polydimethylsiloxane structures through aurethane bond and (B) at least one kind of a pyrrolidone derivative inwhich a polymerizable group is a methylene group.

Further, the present invention relates to a method for preparing anocular lens material, comprising

a) a step of obtaining a mixed solution comprising at least one kind ofa compound (A) having ethylenically unsaturated groups andpolydimethylsiloxane structure through a urethane bond and a hydrophilicmonomer (B) comprising at least one kind of a pyrrolidone derivative inwhich a polymerizable group is a methylene group and an photopolymerization initiator and/or a thermal polymerization initiator,

b) a step of introducing said mixed solution to a mold for molding,

c) a step of obtaining an ocular lens material cured by irradiating UVlight on and/or heating the mixed solution in said mold for molding,

d) a step of carrying out surface treatment to said ocular lens materialafter demolding said ocular lens material to impart hydrophilicity anddeposit resistance,

e) a step of removing an unreacted component from said ocular lensmaterial, and

f) a step of hydrating said ocular lens material.

BEST MODE FOR CARRYING OUT THE INVENTION

The ocular lens material of the present invention comprises at least onekind of a compound (A) having an ethylenically unsaturated group andpolydimethylsiloxane structure through a urethane bond and at least onekind of a pyrrolidone derivative (B) in which a polymerizable group is amethylene group.

The compound (A) has a bond being an elastic urethane bond and is acomponent reinforcing without spoiling flexibility and oxygenpermeability of the material by the siloxane segment, imparting stressrelaxation to remove brittleness and improving mechanical strength.Further, since the compound (A) has silicone chains in its molecularchain, it can impart high oxygen permeability to a product.

Since the compound (A) has ethylenically unsaturated groups being apolymerizable group at each terminal of the molecule, and iscopolymerized with other copolymerization component through thepolymerizable group, it has excellent characteristics of imparting tothe obtained ocular lens material not only physical reinforcing effectby intertwisting of molecule but also reinforcing effect by chemicalbond (covalent bond). Namely, the compound (A) acts as a high molecularweight crosslinkable monomer.

The compound (A) is a polysiloxane macromonomer in which thepolymerizable groups represented by the general formula (1):A¹-U¹-(—S¹—U²—)_(n)—S²—U³-A²  (1)[Wherein A¹ is a group represented by the general formula (2):Y²¹-Z²¹-R³¹-  (2)(Wherein Y²¹ indicates a (meth)acryloyl group, a vinyl group or an allylgroup, Z²¹ indicates an oxygen atom or a direct bond, and R³¹ indicatesa direct bond or an alkylene group having a linear chain, a branchedchain or an aromatic ring having 1 to 12 carbons);

A² is a group represented by the general formula (3):-R³⁴-Z²²-Y²²  (3)(Wherein Y²² indicates a (meth)acryloyl group, a vinyl group or an allylgroup, Z²² indicates an oxygen atom or a direct bond, and R³⁴ indicatesa direct bond or an alkylene group having a linear chain, a branchedchain or an aromatic ring having 1 to 12 carbons) (Provided that Y²¹ inthe general formula (2) and Y²² in the general formula (3) may be thesame or different);

U¹ is a group represented by the general formula (4):-X²¹-E²¹-X²⁵-R³²-  (4)(Wherein each of X²¹ and X²⁵ is independently selected from a directbond, an oxygen atom and an alkylene glycol group, E²¹ is a —NHCO— group(Provided that in this case, X²¹ is a direct bond, X²⁵ is an oxygen atomor an alkylene glycol group, and E²¹ forms a urethane bond with X²⁵), a—CONH— group (Provided that in this case, X²¹ is an oxygen atom or analkylene glycol group, X²⁵ is a direct bond, and E²¹ forms a urethanebond with X²¹), or a divalent group derived from diisocyanate selectedfrom the group consisting of a saturated or unsaturated aliphatic group,an alicyclic group and an aromatic group (Provided that in this case,each of X²¹ and X²⁵ is independently selected from an oxygen atom and analkylene glycol group, and E²¹ forms two urethane bonds with X²¹ andX²⁵), R³² indicates an alkylene group having a linear chain or abranched chain having 1 to 6 carbons);

each of S¹ and S² is independently a group represented by the generalformula (5):

(Wherein each of R²³, R²⁴, R²⁵, R²⁶, R²⁷ and R²⁸ is independently analkyl group having 1 to 6 carbons, an alkyl group substituted withfluorine or a phenyl group, k is an integer of 10 to 100, L is 0 or aninteger of 1 to 90, and K+L is an integer of 10 to 100);

U² is a group represented by the general formula (6):-R³⁷-X²⁷-E²⁴-X²⁸-R³⁸-  (6)(Wherein each of R³⁷ and R³⁸ is independently an alkylene group having alinear chain or a branched chain having 1 to 6 carbons; each of X²⁷ andX²⁸ is independently an oxygen atom or an alkylene glycol group; E²⁴ isa divalent group derived from diisocyanate selected from the groupconsisting of a saturated or unsaturated aliphatic group, an alicyclicgroup and an aromatic group (Provided that in this case, E²⁴ forms twourethane bonds with X²⁷ and X²⁸);

U³ is a group represented by the general formula (7):-R³³-X²⁶-E²²-X²²-  (7)(Wherein R³³ indicates an alkylene group having a linear chain or abranched chain having 1 to 6 carbons, each of X²² and X²⁶ isindependently selected from a direct bond, an oxygen atom and analkylene glycol group, E²² is a —NHCO— group (Provided that in thiscase, X²² is an oxygen atom or an alkylene glycol group, X²⁶ is a directbond, and E²² forms a urethane bond with X²²), a —CONH— group (Providedthat in this case, X²² is a direct bond, X²⁶ is an oxygen atom or analkylene glycol group, and E²² forms a urethane bond with X²⁶), or adivalent group derived from diisocyanate selected from the groupconsisting of a saturated or unsaturated aliphatic group, an alicyclicgroup and an aromatic group (Provided that in this case, each of X²² andX²⁶ is independently selected from an oxygen atom and an alkylene glycolgroup, and E²² forms two urethane bonds with X²² and X²⁶); n indicates 0or an integer of 1 to 10], are bound with a siloxane main chain throughat least one of urethane bonds

In the general formula (1), A¹ is a group represented by the generalformula (2) as described above:Y²¹-Z²¹-R³¹-  (2)(Wherein Y²¹, Z²¹ and R³¹ are the same as the fore-description), and A²is a group represented by the general formula (3):-R³⁴-Z²²-Y²²  (3)(Wherein Y²², Z²² and R³⁴ are the same as the fore-description).

Either of Y²¹ and Y²² is a polymerizable group, and an acryloyl group ispreferable in particular from the viewpoint of capable of being easilycopolymerized with a hydrophilic monomer (D).

Either of Z²¹ and Z²² is an oxygen atom or a direct bond and an oxygenatom is preferable.

Either of R³¹ and R³⁴ are a direct bond or an alkylene group having alinear chain, a branched chain or an aromatic ring having 1 to 12carbons and an alkylene group having 2 to 4 carbons is preferable.

Either of U¹, U² and U³ represents a group containing a urethane groupin the molecular chain of the compound (A).

In U¹ and U³, E²¹ and E²² are respectively a —CONH— group, a —NHCO—group or a divalent group derived from diisocyanate selected from thegroup consisting of a saturated or unsaturated aliphatic group, analicyclic group and an aromatic group. Wherein examples of the divalentgroup derived from diisocyanate selected from the group consisting of asaturated or unsaturated aliphatic group, an alicyclic group and anaromatic group include divalent groups derived from saturated aliphaticdiisocyanate such as ethylene diisocyanate, 1,3-diisocyanate propane andhexamethylene diisocyanate; divalent groups derived from alicyclicdiisocyanate such as 1,2-diisocyanatocyclohexane,bis(4-isocyanatocyclohexyl)methane and isophorone diisocyanate; divalentgroups derived from aromatic diisocyanate such as tolylene diisocyanateand 1,5-diisocyanatonaphthalene; and divalent groups derived fromunsaturated aliphatic diisocyanate such as 2,2′-diisocyanatediethylfumarate. Among these, a divalent group derived from hexamethylenediisocyanate, a divalent group derived from tolylene diisocyanate and adivalent group derived from isophorone diisocyanate are preferablebecause they are comparatively available and strength is easilyimparted.

In U¹, when E²¹ is a —NHCO— group, X²¹ is a direct bond, X²⁵ is anoxygen atom or an alkylene glycol group, and E²¹ forms a urethane bondwhich is represented by the formula: —NHCOO—, with X²⁵. Further, whenE²¹ is a —CONH— group, X²¹ is an oxygen atom or an alkylene glycolgroup, X²⁵ is a direct bond, and E²¹ forms a urethane bond which isrepresented by the formula: —OCONH—, with X²¹. Further, when E²¹ is adivalent group derived from the fore-mentioned diisocyanate, each of X²¹and X²⁵ is independently selected from an oxygen atom and preferably analkylene glycol group having 1 to 6 carbons, and E²¹ forms two urethanebonds with X²¹ and X²⁵. R³² is an alkylene group having a linear chainor a branched chain having 1 to 6 carbons.

In U², E²⁴ represents a divalent group derived from diisocyanateselected from the group consisting of a saturated or unsaturatedaliphatic group, an alicyclic group and an aromatic group, as describedabove. Hereat, examples of the divalent group derived from diisocyanateselected from the group consisting of a saturated or unsaturatedaliphatic group, an alicyclic group and an aromatic group includedivalent groups which are similar as in the fore-mentioned U¹ and U³.Among these, a divalent group derived from hexamethylene diisocyanate, adivalent group derived from tolylene diisocyanate and a divalent groupderived from isophorone diisocyanate are preferable because they arecomparatively available and strength is easily imparted. Further, E²⁴forms two urethane bonds with X²⁷ and X²⁸. Each of X²⁷ and X²⁸ isindependently an oxygen atom or preferably an alkylene glycol grouphaving 1 to 6 carbons, and each of R³⁷ and R³⁸ is independently analkylene group a linear chain or a branched chain having 1 to 6 carbons.

In U³, R³³ is an alkylene group having a linear chain or a branchedchain having 1 to 6 carbons. When E²² is a —NHCO— group, X²² is anoxygen atom or an alkylene glycol group, X²⁶ is a direct bond, and E²²forms a urethane bond which is represented by the formula: —NHCOO—, withX²². Further, when E²² is a —CONH— group, X²² is a direct bond, X²⁶ isan oxygen atom or an alkylene glycol group, and E²² forms a urethanebond which is represented by the formula: —OCONH—, with X²⁶. Further,when E²² is a divalent group derived from the fore-mentioneddiisocyanate, each of X²² and X²⁶ is independently selected from anoxygen atom or preferably an alkylene glycol group having 1 to 6carbons, and E²² forms two urethane bonds with X²² and X²⁶.

Hereat, the example of alkylene glycol having preferably 1 to 20 carbonsin the fore-mentioned X²¹, X²⁵, X²⁷, X²⁸, X²² and X²⁶ includes a grouprepresented by the general formula (8) and the like:—O—(C_(x)H_(2x)—O)_(y)—  (8)(Wherein x indicates an integer of 1 to 4 and y indicates an integer of1 to 5).

Either of S¹ and S² is a group represented by the general formula (5),as described above.

In the general formula (5), each of R²³, R²⁴, R²⁵, R²⁶, R²⁷ and R²⁸ isindependently an alkyl group having 1 to 6 carbons, an alkyl groupsubstituted with fluorine or a phenyl group.

The example of the alkyl group substituted with fluorine includes agroup represented by —(CH₂)_(m)—C_(n)F_(2n+1)(m=1 to 10, n=1 to 10), andits specific example includes, for example, side chain alkyl groupssubstituted with fluorine such as a 3,3,3-trifluoro-n-propyl group, a2-(perfluorobutyl)ethyl group and 2-(perfluorooctyl)ethyl group; andbranched chain alkyl groups substituted with fluorine such as a2-(perfluoro-5-methylhexyl)ethyl group, etc. Further, in the presentinvention, when the compound (A) having such an alkyl group substitutedwith fluorine is used and its content is increased, the lipid-depositresistance of the ocular lens material obtained tends to be improved.

Further, k is an integer of 10 to 100 and L is 0 or an integer of 1 to90. K+L is preferably an integer of 10 to 100 and more preferably 10 to80. When K+L is larger than 100, the molecular weight of the compound(A) is enlarged, its solubility to a pyrrolidone derivative and ahydrophilic monomer other than this is deteriorated, they are nothomogeneously dissolved at mixing, and phase separation occurs atpolymerization to be opaque; therefore a homogeneous and transparentocular lens material tends to be not obtained. Further, when K+L is lessthan 10, the oxygen permeability of the ocular lens material obtained islowered and its flexibility tends to be lowered.

Further, n is preferably 0 or an integer of 1 to 10. When n is largerthan 10, the molecular weight of the compound (A) is enlarged, itssolubility with a pyrrolidone derivative and a hydrophilic monomer otherthan this is deteriorated, they are not homogeneously dissolved atmixing, and phase separation occurs at polymerization to be opaque;therefore a homogeneous and transparent ocular lens material tends to benot obtained. The symbol n is more preferably 0 or an integer of 1 to 5.

Further, the compound (A) is a polysiloxane macromonomer in which thepolymerizable groups represented by the general formula (9):A¹-U¹-T¹-U⁴-(—S¹—U²—)_(n)—S²—U⁵-T²-U³-A²  (9)(Wherein A¹, A², U¹, U², U³, S¹, S² and n are the same as the generalformula (1), and U⁴ and U⁵ are respectively the same as U¹ and U³.Provided that Y²¹ and Y²² in A¹ and A² are a (meth)acryloyl group, avinyl group or an allyl group.)

T¹ and T² are a segment containing a hydrophilic polymer or a segmentcontaining a hydrophilic oligomer represented by the general formula(10):-Q-(CH₂CHD-Q-)_(n)-  (10)(Wherein D is a hydrogen atom, a methyl group or a hydroxy group, Q is adirect bond or an oxygen atom, and n is 5 to 10000), or the generalformula (11):-(M)x-  (11)(Wherein M indicates a hydrophilic monomer unit selected from 1,3-MMP,N-VP, (meth)acrylic acid, (meth)acrylic acid salt,N,N-dimethylacrylamide, N,N-diethylacrylamide, 2-hydroxyethyl(meth)acrylate, tetrahydrofuran, oxetane, oxazoline,2-methacryloyloxyethyl phosphoryl choline and the like, and apolymerization chain of the polymer composed by these units may be alinear chain or a branched chain and may be random or block. X is 5 to10000))are bound with a siloxane main chain through at least one of urethanebonds.

The compound (A) may further have a hydrophilic polymer structure. Thesolubility of the compound (A) with a hydrophilic monomer is improved bythe structure, and the wettability of a material comprising these can beimproved. The structure of the hydrophilic polymer unit includes atleast one of polymers obtained by polymerizing monomers, for example,polyethylene glycol, polypropylene glycol, polyvinyl alcohol,polyvinylpyrrolidone, poly(meth)acrylic acid, poly(meth)acrylate,poly(2-hydroxyethyl(meth)acrylate), polytetrahydrofuran, polyoxetane,polyoxazoline, polydimethyl acrylamide, polydiethylacrylamide andpolymers containing a zwitter ionic group such aspoly(2-methacryloyloxyethyl phosphoryl choline). The molecular weight ofthe hydrophilic polymer structural unit is 100 to 1000000 and preferably1000 to 500000. When the molecular weight is less than 100,hydrophilicity enough for dissolving the compound (A) in a hydrophilicmonomer tends to be unable to be imparted. On the other hand, when themolecular weight exceeds 1000000, both of hydrophilic domain andhydrophobic domain is enlarged and a transparent material tends to benot obtained.

The typical example of the compound (A) includes, for example, acompound represented by the formula (hereinafter, referred to as thecompound (A-1)):

a compound represented by the formula (hereinafter, referred to as thecompound (A-2)):

and the like. These can be used alone or a mixture of 2 or more ofcompounds can be used.

At least one of pyrrolidone derivatives (B) in which the polymerizablegroup is a methylene group which is used in the present invention, forexample, 1-alkyl-3-methylene-2-pyrrolidone,1-alkyl-5-methylene-2-pyrrolidone, and 5-alkyl-3-methylene-2-pyrrolidoneis a component which imparts excellent flexibility and wettability to anocular lens material and improves patient comfort. Further, in thereaction system, since at least one of pyrrolidone derivatives (B) inwhich the polymerizable group is a methylene group has higherpolymerizability in comparison with a case that N-vinyl pyrrolidonebeing a hydrophilic monomer is used, the elution of an unreacted monomerand the like which remain in a product material can be suppressed at alow level. When the use amount of at least one of pyrrolidonederivatives (B) is increased, excellent surface wettability and thelubricity/easy lubricating property of surface can be imparted to theocular lens material. Specifically, the use amount of at least one ofpyrrolidone derivatives (B) is preferably 5 to 60% by weight based onthe total polymerizable components and more preferably 10 to 55% byweight. When the use amount of at least one of pyrrolidone derivatives(B) is less than 5% by weight, desired surface wettability and thelubricity/easy lubricating property of surface cannot be achieved andthe wettability of material surface tends to be inferior. On the otherhand, when it exceeds 60% by weight, oxygen permeability is dominated bywater content, adequate oxygen tends to be not supplied to the corneaconsidering the wearing state at continuous wearing or at short sleep.

The at least one of pyrrolidone derivatives (B) in which thepolymerizable group is a methylene group which is used in the presentinvention includes 1-methyl-3-methylene-2-pyrrolidone,1-ethyl-3-methylene-2-pyrrolidone, 1-methyl-5-methylene-2-pyrrolidone,1-ethyl-5-methylene-2-pyrrolidone, 5-methyl-3-methylene-2-pyrrolidone,5-ethyl-3-methylene-2-pyrrolidone, 1-n-propyl-3-methylene-2-pyrrolidone,1-n-propyl-5-methylene-2-pyrrolidone,1-isopropyl-3-methylene-2-pyrrolidone,1-isopropyl-5-methylene-2-pyrrolidone,1-n-butyl-3-methylene-2-pyrrolidone,1-tert-butyl-3-methylene-2-pyrrolidone and the like, but is not limitedto these. These can be used alone or 2 or more can be used incombination. Among these at least one of pyrrolidone derivatives (B) inwhich the polymerizable group is a methylene group,1-methyl-3-methylene-2-pyrrolidone, 1-methyl-5-methylene-2-pyrrolidoneand 5-methyl-3-methylene-2-pyrrolidone are preferable from theviewpoints that excellent hydrophilicity, a material superior in thehydrophilicity is obtained by using a small amount and its preparingmethod is comparatively easy.

In order to further improve the oxygen permeability of an obtainedocular lens material and impart flexibility in the present invention, asilicone compound (C) other than the fore-mentioned compound (A) ispreferably comprised as the ocular lens material.

The silicone compound (C) includes silicone-containing alkyl(meth)acrylate, silicone-containing styrene derivative and diesters ofsilicone-containing fumaric acid. These can be used alone or 2 or moreof compounds can be used in combination.

Further, “˜(meth)acrylate” described in the present specification means“˜acrylate and/or ˜methacrylate”, and other (meth)acrylate derivative isalso similar.

Examples of the silicone-containing alkyl (meth)acrylate includetrimethylsiloxydimethylsilylmethyl (meth)acrylate,trimethylsiloxydimethylsilylpropyl (meth)acrylate,methylbis(trimethylsiloxy)silylpropyl (meth)acrylate,tris(trimethylsiloxy)silylpropyl (meth)acrylate, mono[methylbis(trimethylsiloxy)siloxy]bis(trimethylsiloxy)silylpropyl(meth)acrylate, tris [methylbis(trimethylsiloxy)siloxy]silylpropyl(meth)acrylate, methylbis(trimethylsiloxy)silylpropylglyceryl(meth)acrylate, tris(trimethylsiloxy)silylpropylglyceryl (meth)acrylate,mono[methylbis(trimethylsiloxy)siloxy]bis(trimethylsiloxy)silylpropylglyceryl(meth)acrylate, trimethylsilylethyltetramethyldisiloxypropylglyceryl(meth)acrylate, trimethylsilylmethyl (meth)acrylate,trimethylsilylpropyl (meth)acrylate, trimethylsilylpropylglyceryl(meth)acrylate, trimethylsiloxydimethylsilylpropylglyceryl(meth)acrylate,methylbis(trimethylsiloxy)silylethyltetramethyldisiloxymethyl(meth)acrylate, tetramethyltriisopropylcyclotetrasiloxanylpropyl(meth)acrylate,tetramethyltriisopropylcyclotetrasiloxybis(trimethylsiloxy) silylpropyl(meth)acrylate and the like.

Examples of the silicone-containing styrene derivative include acompound represented by the general formula (12):

(Wherein p indicates an integer of 1 to 15, q indicates 0 or 1, and rindicates an integer of 1 to 15). In the silicone-containing styrenederivative represented by the general formula (12), when p or r is aninteger of 16 or more, purification and synthesis are difficult and thehardness of the ocular lens material obtained tends to be lowered.Further, when q is an integer of 2 or more, synthesis of thesilicone-containing styrene derivative tends to be difficult.

Examples of the silicone-containing styrene derivative represented bythe fore-mentioned general formula (12) includetris(trimethylsiloxy)silylstyrene,bis(trimethylsiloxy)methylsilylstyrene,(trimethylsiloxy)dimethylsilylstyrene,tris(trimethylsiloxy)siloxydimethylsilylstyrene,[bis(trimethylsiloxy)methylsiloxy]dimethylsilylstyrene,(trimethylsiloxy)dimethylsilylstyrene, heptamethyltrisiloxanylstyrene,nonamethyltetrasiloxanylstyrene, pentadecamethylheptasiloxanylstyrene,heneicosamethyldecasiloxanylstyrene,heptacosamethyltridecasiloxanylstyrene,hentriacontamethylpentadecasiloxanylstyrene,trimethylsiloxypentamethyldisiloxymethylsilylstyrene,tris(pentamethyldisiloxy)silylstyrene,tris(trimethylsiloxy)siloxybis(trimethylsiloxy)silylstyrene,bis(heptamethyltrisiloxy)methylsilylstyrene,tris[methylbis(trimethylsiloxy)siloxy]silylstyrene, trimethylsiloxybis[tris(trimethylsiloxy)siloxy]silylstyrene,heptakis(trimethylsiloxy)trisilylstyrene,nonamethyltetrasiloxyundecylmethylpentasiloxymethylsilylstyrene,tris[tris(trimethylsiloxy)siloxy]silylstyrene,(tristrimethylsiloxyhexamethyl)tetrasiloxy[tris(trimethylsiloxy)siloxy]trimethylsiloxysilylstyrene, nonakis(trimethylsiloxy)tetrasilylstyrene,bis(tridecamethylhexasiloxy)methylsilylstyrene,heptamethylcyclotetrasiloxanylstyrene,hepatamethylcyclotetrasiloxybis(trimethylsiloxy)silylstyrene,tripropyltetramethylcyclotetrasiloxanylstyrene, trimethylsilylstyreneand the like.

Examples of the silicone-containing fumaric acid diester include acompound represented by the general formula (13):

(Wherein each of R¹, R², R³, R⁴, R⁵ and R⁶ indicates independently amethyl group, a trimethylsiloxy group represented by the formula:

and each of m and n indicates an integer of 1 to 3).

Examples of the fore-mentioned compound represented by the generalformula (13) include bis(3-(trimethylsilyl)propyl)fumarate,bis(3-(pentamethyldisiloxanyl)propyl)fumarate,bis(3-((1,3,3,3-tetramethyl-1-trimethylsiloxy)disiloxanyl)propyl)fumarate,bis(tris(trimethylsiloxy)silylpropyl)fumarate, and the like. These canbe used alone or a mixture of 2 or more of compounds can be used.

Among these, the silicone-containing alkyl (meth)acrylate is preferablefrom the viewpoints of imparting the flexibility to a material and thecopolymerizability with the compound (A) and the pyrrolidone compound(B), and tris(trimethylsiloxy)silylpropyl (meth)acrylate is morepreferable from the viewpoints of imparting the polymerizability, oxygenpermeability and flexibility.

The use amount of the silicone-containing alkyl (meth)acrylate among thesilicone compound (C) is preferably 3 to 65% by weight based on thetotal polymerizable components and more preferably 5 to 60% by weight.When the use amount of the silicone-containing alkyl (meth)acrylate isless than 3% by weight, the ocular lens material obtained is highmodulus and brittle and tends to be inferior in flexibility. On theother hand, when it exceeds 65% by weight, modulus is lowered but therepulsive property is inferior and adhesion of surface tends to beincreased.

The use amount of the silicone-containing styrene derivative among thesilicone compound (C) is preferably 1 to 30% by weight based on thetotal polymerizable components and more preferably 3 to 20% by weight.When the use amount of the silicone-containing styrene derivative isless than 1% by weight, the oxygen permeability and mechanical strengthof the ocular lens material obtained tend to be unable to be adequatelyimproved. On the other hand, when it exceeds 30% by weight, theflexibility of the ocular lens material obtained tends to be lowered.

The use amount of the silicone-containing fumaric acid diester among thesilicone compound (C) is preferably 1 to 50% by weight based on thetotal polymerizable components and more preferably 3 to 40% by weight.When the use amount of the silicone-containing fumaric acid diesters isless than 1% by weight, the oxygen permeability of the ocular lensmaterial obtained tend to be unable to be adequately improved. On theother hand, when it exceeds 50% by weight, adequate mechanical strengthtends to be not obtained.

It is preferable that the ocular lens material of the present inventioncontains N-substituted acrylamide (D). When N-substituted acrylamide (D)is contained as the ocular lens material, it functions as thesolubilizer of the silicone component together with the pyrrolidonecompound (B), and a homogeneous hydrogel superior in transparency can beprepared. Only the pyrrolidone derivative (B) without using theN-substituted acrylamide (D) is inferior in solubility with thesilicone-containing components such as the compound (A) and the siliconecompound (C), and the transparency of the ocular lens material obtainedtend to be lowered. To the contrary, in the present invention, thesolubility with the silicone-containing compound is improved bysimultaneously using the N-substituted acrylamide (D) together with thepyrrolidone derivative (B) and the transparency of the ocular lensmaterial obtained can be improved.

The N-substituted acrylamide (D) includes N,N-dimethyl acrylamide,N,N-diethyl acrylamide, N-(2-hydroxyethyl) acrylamide, N-isopropylacrylamide, acryloyl morpholine and the like. Among these, N,N-dimethylacrylamide, N,N-diethyl acrylamide and acryloyl morpholine arepreferable from the viewpoint of improving the solubility at a smallamount.

In the present invention, the use amount of the N-substituted acrylamide(D) is preferably 3 to 40% by weight based on the total polymerizablecomponents and more preferably 5 to 35% by weight. When the use amountof the N-substituted acrylamide (D) is less than 3% by weight, thepolymer becomes opaque and the oxygen permeability of the ocular lensmaterial tends to be lowered. On the other hand, when it exceeds 40% byweight, the N-substituted acrylamide takes in much lipid in the tearfluid because of amphiphatic property and the ocular lens tends to bestained. At this time, when the use amount of the pyrrolidone derivative(B) is lessened for further obtaining desired oxygen permeability, thewettability and lubricity of surface of an ocular lens material tends tobe poor.

When the pyrrolidone derivative (B) and the N-substituted acrylamide (D)are used in combination as the ocular lens material of the presentinvention, the ratio of the pyrrolidone derivative (B) to theN-substituted acrylamide (D) [(B)/(D) (weight ratio)] is preferably atleast 40/60, more preferably at least 45/55, and further preferably atleast 50/50, because the wettability and lubricity/easy lubricatingproperty of surface of the ocular lens material is feared to be poorwhen the content of pyrrolidone derivative (B) is low. Further, when thecontent of pyrrolidone derivative (B) is high, the ratio is preferablyat most 100/0, more preferably at most 95/5 and further preferably atmost 90/10 because the polymer becomes opaque, the transparency of theocular lens material is lowered, the hardness of the material itself isheightened and the patient comfort is feared to be adversely affected.

When the silicone compound (C) and the N-substituted acrylamide (D) arefurther comprised in addition to the compound (A) and the pyrrolidonederivative (B) as the ocular lens material of the present invention, therespective ratios are preferably set as follow. The ratio of the sum ofthe compound (A) and the silicone compound (C) to the sum of thepyrrolidone derivative (B) and the N-substituted acrylamide (D)[{(A)+(C)}/{(B)+(D)} (weight ratio)] is preferably at least 30/70, morepreferably at least 35/65 and further preferably at least 40/60 becausethe oxygen permeability of the ocular lens material depends on watercontent and the high oxygen permeability is impossible to be obtainedwhen (B)+(D) is much. Further, the proportion is preferably at most70/30, more preferably at most 67/33 and further preferably at most65/35 because the flexibility of the ocular lens material is lost,obtained material has stiffness and sticky surface, patient comfort isadversely affected when (A)+(C) is much.

As a condition simultaneously required together with[{(A)+(C)}/{(B)+(D)} (weight ratio)] of the ratio of {(A)+(C)} to{(B)+(D)}, the ratio of the compound (A) to the silicone compound (C)[(A)/(C) (weight ratio)] is preferably at least 25/75, more preferablyat least 27/73 and further preferably at least 30/70 because the surfaceof the ocular lens material becomes extremely sticky and shape stabilityof the material is lowered when the silicone compound (C) is much. Theratio is preferably at most 75/25, more preferably at most 73/27 andfurther preferably at most 70/30 because the ocular lens material haslow flexibility, stiffness and brittleness when the compound (A) ismuch.

Further, in the present invention, a hydrophilic monomer (E) other thanthe N-substituted acrylamide (D) which is copolymerized together withthe pyrrolidone derivative (B) can be used. When the hydrophilic monomer(E) is comprised in the ocular lens material, the flexibility andwettability of surface are imparted to the ocular lens materialobtained, the patient comfort is improved and the lubricity/easylubricating property can be further imparted.

Examples of the hydrophilic monomer (E) usable in the present inventioninclude (meth)acrylamide, hydroxyalkyl (meth)acrylate such as2-hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate andhydroxybutyl (meth)acrylate; (alkyl)aminoalkyl (meth)acrylate such as2-dimethylaminoethyl (meth)acrylate and 2-butylaminoethyl(meth)acrylate; alkyleneglycol mono(meth)acrylate such as ethyleneglycolmono(meth)acrylate and propyleneglycol mono(meth)acrylate;polyalkyleneglycol mono(meth)acrylate such as polyethyleneglycolmono(meth)acrylate and polypropyleneglycol mono(meth)acrylate;ethyleneglycol allyl ether; ethyleneglycol vinyl ether; (meth)acrylicacid; aminostyrene; hydroxystyrene; vinyl acetate; glycidyl(meth)acrylate; allylglycidyl ether; vinyl propionate;N,N-dimethylmethacrylamide, N,N-diethylmethacrylamide,N-(2-hydroxyethyl) methacrylamide, N-isopropylmethacrylamide,methacroylmorpholine; N-vinyllactam such as N-vinyl-2-pyrrolidone,N-vinyl-3-methyl-2-pyrrolidone, N-vinyl-4-methyl-2-pyrrolidone,N-vinyl-5-methyl-2-pyrrolidone, N-vinyl-6-methyl-2-pyrrolidone,N-vinyl-3-ethyl-2-pyrrolidone, N-vinyl-4,5-dimethyl-2-pyrrolidone,N-vinyl-5,5-dimethyl-2-pyrrolidone,N-vinyl-3,3,5-trimethyl-2-pyrrolidone, N-vinyl-2-piperidone,N-vinyl-3-methyl-2-piperidone, N-vinyl-4-methyl-2-piperidone,N-vinyl-5-methyl-2-piperidone, N-vinyl-6-methyl-2-piperidone,N-vinyl-6-ethyl-2-piperidone, N-vinyl-3,5-dimethyl-2-piperidone,N-vinyl-4,4-dimethyl-2-piperidone, N-vinyl-2-caprolactam,N-vinyl-3-methyl-2-caprolactam, N-vinyl-4-methyl-2-caprolactam,N-vinyl-7-methyl-2-caprolactam, N-vinyl-7-ethyl-2-caprolactam,N-vinyl-3,5-dimethyl-2-caprolactam, N-vinyl-4,6-dimethyl-2-caprolactamand N-vinyl-3,5,7-trimethyl-2-caprolactam; N-vinylamide such asN-vinylformamide, N-vinyl-N-methylformamide, N-vinyl-N-ethylformamide,N-vinylacetamide, N-vinyl-N-methylacetamide, N-vinyl-N-ethylacetamideand N-vinylphthalimide, and the like. Among these hydrophilic monomers(E), (meth)acrylamide, hydroxyalkyl (meth)acrylate, alkyleneglycol(meth)acrylate, (meth)acrylic acid, N-vinyllactam and N-vinylamide arepreferable from the viewpoints that solubility with thesilicone-containing compound is superior and wettability is imparted tothe ocular lens material. These can be used alone or a mixture of 2 ormore of compounds can be used.

Further, for example, when the ocular lens material is prepared and thentreated with an acid or a base in a system using a component such asvinyl acetate which is subject to hydrolysis by an acid or base, furtherflexibility and surface wettability can be imparted to the ocular lensmaterial.

When desired property is further imparted to the ocular lens materialobtained, alkyl (meth)acrylate, fluorine-containing alkyl(meth)acrylate, a monomer for adjusting hardness, a polymerizable or nonpolymerizable ultraviolet absorbent, a dyestuff, an ultravioletabsorbing dyestuff and the like can be also used as a monomer (F).

Alkyl (meth)acrylate is a component for adjusting the hardness of theocular lens material to impart hardness and softness.

Examples of the alkyl (meth)acrylate include linear, branched or cyclicalkyl (meth)acrylate such as methyl (meth)acrylate, ethyl(meth)acrylate, isopropyl (meth)acrylate, n-propyl (meth)acrylate,isobutyl (meth)acrylate, n-butyl (meth)acrylate, 2-ethylhexyl(meth)acrylate, n-octyl (meth)acrylate, n-decyl (meth)acrylate,n-dodecyl (meth)acrylate, tert-butyl (meth)acrylate, pentyl(meth)acrylate, tert-pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl(meth)acrylate, nonyl (meth)acrylate, stearyl (meth)acrylate,cyclopentyl (meth)acrylate and cyclohexyl (meth)acrylate. These can beused alone or a mixture of 2 or more of compounds can be used.

Fluorine-containing alkyl (meth)acrylate is a component for improvingthe lipid-deposit resistance of the ocular lens material.

Examples of the fluorine-containing alkyl (meth)acrylate includes acompound represented by the general formula (14):CH₂═CR⁴COOC_(s)H_((2s−t+1))F_(t)  (14)(Wherein R⁴ indicates a hydrogen atom or CH₃, s indicates an integer of1 to 15, t indicates an integer of 1 to (2s+1)).

Specific examples of the fore-mentioned general formula (14) include,for example, 2,2,2-trifluoroethyl (meth)acrylate,2,2,3,3-tetrafluoropropyl (meth)acrylate, 2,2,3,3-tetrafluoro-t-pentyl(meth)acrylate, 2,2,3,4,4,4-hexafluorobutyl (meth)acrylate,2,2,3,4,4,4-hexafluoro-t-hexyl(meth)acrylate,2,3,4,5,5,5-hexafluoro-2,4-bis(trifluoromethyl)pentyl(meth)acrylate,2,2,3,3,4,4-hexafluorobutyl (meth)acrylate,2,2,2,2′,2′,2′-hexafluoroisopropyl (meth)acrylate,2,2,3,3,4,4,4-heptafluorobutyl (meth)acrylate,2,2,3,3,4,4,5,5-octafluoropentyl (meth)acrylate,2,2,3,3,4,4,5,5,5-nonafluoropentyl (meth)acrylate,2,2,3,3,4,4,5,5,6,6,7,7-dodecafluoroheptyl (meth)acrylate,3,3,4,4,5,5,6,6,7,7,8,8-dodecafluorooctyl (meth)acrylate,3,3,4,4,5,5,6,6,7,7,8,8,8-tridecafluorooctyl (meth)acrylate,2,2,3,3,4,4,5,5,6,6,7,7,7-tridecafluoroheptyl (meth)acrylate,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10-hexadecafluorodecyl (meth)acrylate,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl(meth)acrylate,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11-octadecafluoroundecyl(meth)acrylate,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-nonadecafluoroundecyl(meth)acrylate,3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12-eicosafluorododecyl(meth)acrylate and the like. These can be used alone or a mixture of 2or more of compounds can be used.

The contents of the alkyl (meth)acrylate and fluorine-containing alkyl(meth)acrylate are preferably at most 20% by weight based on the totalpolymerizable components and more preferably at most 10% by weight sothat the effect by polymerization components such as the compound (A)and the pyrrolidone derivative (B) being essential components, further,the silicone compound (C), the N-substituted acrylamide (D) and thehydrophilic monomer (E) is expressed. Further, the contents are at least0.01% by weight based on the fore-mentioned components and preferably atleast 0.1% by weight in order to adequately express the effect of thealkyl (meth)acrylate and the fluorine-containing alkyl (meth)acrylate.

The monomer for adjusting hardness is a component adjusting the hardnessof the ocular lens material and imparting hardness and softness.

Examples of the monomer for adjusting hardness include alkoxyalkyl(meth)acrylate such as 2-ethoxyethyl (meth)acrylate, 3-ethoxypropyl(meth)acrylate, 2-methoxyethyl (meth)acrylate and 3-methoxypropyl(meth)acrylate; alkylthio alkyl (meth)acrylate such as ethylthioethyl(meth)acrylate and methylthioethyl (meth)acrylate; styrene;α-methylstyrene; alkyl styrene such as methylstyrene, ethylstyrene,propylstyrene, butylstyrene, t-butylstyrene, isobutylstyrene andpentylstyrene; alkyl-α-methylstyrene such as methyl-α-methylstyrene,ethyl-α-methylstyrene, propyl-α-methylstyrene, butyl-α-methylstyrene,t-butyl-α-methylstyrene, isobutyl-α-methylstyrene andpentyl-α-methylstyrene, and the like. These can be used alone or amixture of 2 or more of compounds can be used.

The content of the monomer for adjusting hardness is at least 1% byweight and preferably at least 3% by weight in order to adequatelyimpart desired hardness and softness for the ocular lens material.Further, the content is at most 30% by weight and preferably at most 20%by weight in order not to lower the oxygen permeability and mechanicalstrength of the ocular lens material.

The polymerizable or non polymerizable ultraviolet absorbent, thedyestuff, and the ultraviolet absorbing dyestuff are components forimparting ultraviolet absorption property to the ocular lens materialand coloring the material.

Specific examples of the fore-mentioned polymerizable or nonpolymerizable ultraviolet absorbent include polymerizable benzophenonetype ultraviolet absorbents such as2-hydroxy-4-(meth)acryloyloxybenzophenone,2-hydroxy-4-(meth)acryloyloxy-5-t-butylbenzophenone,2-hydroxy-4-(meth)acryloyloxy-2′,4′-dichlorobenzophenone,2-hydroxy-4-(2′-hydroxy-3′-(meth)acryloyloxypropoxy)benzophenone;polymerizable benzotriazole type ultraviolet absorbents such as2-(2′-hydroxy-5′-(meth)acryloyloxyethylphenyl)-2H-benzotriazole,2-(2′-hydroxy-5′-(meth)acryloyloxyethylphenyl)-5-chloro-2H-benzotriazole,2-(2′-hydroxy-5′-(meth)acryloyloxypropylphenyl)-2H-benzotriazole,2-(2′-hydroxy-5′-(meth)acryloyloxypropylphenyl-3′-t-butylphenyl)-5-chloro-2H-benzotriazoleand2-(2′-hydroxy-5′-(2″-methacryloyloxyethoxy)-3′-t-butylphenyl)-5-methyl-2H-benzotriazole;polymerizable salicylic acid type ultraviolet absorbents such as2-hydroxy-4-methacryloyloxymethyl phenylbenzoate;2-cyano-3-phenyl-3-(3′-(meth)acryloyloxyphenyl)propenylic acid methylester and the like. These can be used alone or a mixture of 2 or more ofcompounds can be used.

Specific examples of the fore-mentioned polymerizable dyestuff includepolymerizable azo type dyestuff such as1-phenylazo-4-(meth)acryloyloxynaphthalene,1-phenylazo-2-hydroxy-3-(meth)acryloyloxynaphthalene,1-naphthylazo-2-hydroxy-3-(meth)acryloyloxynaphthalene,1-(α-anthrylazo)-2-hydroxy-3-(meth)acryloyloxynaphthalene,1-((4′-(phenylazo)-phenyl)azo)-2-hydroxy-3-(meth)acryloyloxynaphthalene,1-(2′,4′-xylylazo)-2-(meth)acryloyloxynaphthalene,1-(o-tolylazo)-2-(meth)acryloyloxynaphthalene,2-(m-(meth)acryloylamide-anilino)-4,6-bis(1′-(o-tolylazo)-2′-naphthylamino)-1,3,5-triazine,2-(m-vinylanilino)-4-(4′-nitrophenylazo)-anilino)-6-chloro-1,3,5-triazine,2-(1′-(o-tolylazo)-2′-naphthyloxy)-4-(m-vinylanilino)-6-chloro-1,3,5-triazine,2-(p-vinylanilino)-4-(1′-(o-tolylazo)-2′-naphthylamino)-6-chloro-1,3,5-triazine,N-(1′-(o-tolylazo)-2′-naphthyl)-3-vinyl phthalic acid monoamide,N-(1′-(o-tolylazo)-2′-naphthyl)-6-vinyl phthalic acid monoamide,3-vinylphthalic acid-(4′-(p-sulfophenylazo)-1′-naphthyl) monoester,6-vinylphthalic acid-(4′-(p-sulfophenylazo)-1′-naphthyl) monoester,3-(meth)acryloylamide-4-phenylazophenol,3-(meth)acryloylamide-4-(8′-hydroxy-3′,6′-disulfo-1′-naphthylazo)-phenol,3-(meth)acryloylamide-4-(1′-phenylazo-2′-naphthylazo)-phenol,3-(meth)acryloylamide-4-(p-tolylazo)-phenol,2-amino-4-(m-(2′-hydroxy-1′-naphthylazo)anilino)-6-isopropenyl-1,3,5-triazine,2-amino-4-(N-methyl-p-(2′-hydroxy-1′-naphthylazo)anilino)-6-isopropenyl-1,3,5-triazine,2-amino-4-(m-(4′-hydroxy-1′-phenylazo)anilino)-6-isopropenyl-1,3,5-triazine,2-amino-4-(N-methyl-p-(4′-hydroxyphenylazo)anilino)-6-isopropenyl-1,3,5-triazine,2-amino-4-(m-(3′-methyl-1′-phenyl-5′-hydroxy-4′-pyrrazolylazo)anilino)-6-isopropenyl-1,3,5-triazine,2-amino-4-(N-methyl-p-(3′-methyl-1′-phenyl-5′-hydroxy-4′-pyrrazolylazo)anilino)-6-isopropenyl-1,3,5-triazine,2-amino-4-(p-phenylazoanilino)-6-isopropenyl-1,3,5-triazine and4-phenylazo-7-(meth) acryloylamide-1-naphthol; polymerizableanthraquinone type dyestuff such as1,5-bis((meth)acryloylamino)-9,10-anthraquinone,1-(4′-vinylbenzoylamide)-9,10-anthraquinone,4-amino-1-(4′-vinylbenzoylamide)-9,10-anthraquinone,5-amino-1-(4′-vinylbenzoylamide)-9,10-anthraquinone,8-amino-1-(4′-vinylbenzoylamide)-9,10-anthraquinone,4-nitro-1-(4′-vinylbenzoylamide)-9,10-anthraquinone, 4-hydroxy-1-(4′-vinylbenzoylamide)-9,10-anthraquinone,1-(3′-vinylbenzoylamide)-9,10-anthraquinone,1-(2′-vinylbenzoylamide)-9,10-anthraquinone,1-(4′-isopropenylbenzoylamide)-9,10-anthraquinone,1-(3′-isopropenylbenzoylamide)-9,10-anthraquinone,1-(2′-isopropenylbenzoylamide)-9,10-anthraquinone,1,4-bis(4′-vinylbenzoylamide)-9,10-anthraquinone,1,4-bis(4′-isopropenylbenzoylamide)-9,10-anthraquinone,1,5′-bis(4′-vinylbenzoylamide)-9,10-anthraquinone,1,5-bis(4′-isopropenylbenzoylamide)-9,10-anthraquinone,1-methylamino-4-(3′-vinylbenzoylamide)-9,10-anthraquinone,1-methylamino-4-(4′-vinylbenzoyloxyethylamino)-9,10-anthraquinone,1-amino-4-(3′-vinylphenylamino)-9,10-anthraquinone-2-sulfonic acid,1-amino-4-(4′-vinylphenylamino)-9,10-anthraquinone-2-sulfonic acid,1-amino-4-(2′-vinylbenzylamino)-9,10-anthraquinone-2-sulfonic acid,1-amino-4-(3′-(meth)acryloylaminophenylamino)-9,10-anthraquinone-2-sulfonicacid,1-amino-4-(3′-(meth)acryloylaminobenzylamino)-9,10-anthraquinone-2-sulfonicacid, 1-(β-ethoxycarbonylallylamino)-9,10-anthraquinone,1-(β-carboxyallylamino)-9,10-anthraquinone,1,5-di-(β-carboxyallylamino)-9,10-anthraquinone,1-(β-isopropoxycarbonylallylamino)-5-benzoylamide-9,10-anthraquinone,2-(3′-(meth)acryloyamide-anilino)-4-(3′-(3″-sulfo-4″-aminoanthraquinon-1″-yl-amino-anilino)-6-chloro-1,3,5-triazine,2-(3′-(meth)acryloyamide-anilino)-4-(3′-(3″-sulfo-4″-aminoanthraquinon-1″-yl)-amino-anilino)-6-hydrazino-1,3,5-triazine,2,4-bis((4′-methoxyanthraquinon-1″-yl)-amino)-6-(3′-vinylanilino)-1,3,5-triazineand2-(2′-vinylphenoxy)-4-(4′-(3″-sulfo-4″-aminoanthraquinon-1″-yl-amino)-anilino)-6-chloro-1,3,5-triazine;polymerizable nitro type dyestuff such as o-nitroanilinomethyl(meth)acrylate; polymerizable phthalocyanine type dyestuff such as(meth)acryloyl-modified tetramino copper phthalocyanine and(meth)acryloyl-modified (dodecanoyl-modified tetramino copperphthalocyanine), etc. These can be used alone or a mixture of 2 or moreof compounds can be used.

Specific examples of the fore-mentioned polymerizable ultravioletabsorbing dyestuff include polymerizable benzophenone type ultravioletabsorbing dyestuff such as 2,4-dihydroxy-3(p-styrenoazo)benzophenone,2,4-dihydroxy-5-(p-styrenoazo)benzophenone,2,4-dihydroxy-3-(p-(meth)acryloyloxymethylphenylazo)benzophenone,2,4-dihydroxy-5-(p-(meth)acryloyloxymethylphenylazo)benzophenone,2,4-dihydroxy-3-(p-(meth)acryloyloxyethylphenylazo)benzophenone,2,4-dihydroxy-5-(p-(meth)acryloyloxyethylphenylazo)benzophenone,2,4-dihydroxy-3-(p-(meth)acryloyloxypropylphenylazo)benzophenone,2,4-dihydroxy-5-(p-(meth)acryloyloxypropylphenylazo)benzophenone,2,4-dihydroxy-3-(o-(meth)acryloyloxymethylphenylazo)benzophenone,2,4-dihydroxy-5-(o-(meth)acryloyloxymethylphenylazo)benzophenone,2,4-dihydroxy-3-(o-(meth) acryloyloxyethylphenylazo)benzophenone,2,4-dihydroxy-5-(o-(meth)acryloyloxyethylphenylazo)benzophenone,2,4-dihydroxy-3-(o-(meth)acryloyloxypropylphenylazo)benzophenone,2,4-dihydroxy-5-(o-(meth)acryloyloxypropylphenylazo)benzophenone,2,4-dihydroxy-3-(p-(N,N-di(meth)acryloyloxyethylamino)phenylazo)benzophenone,2,4-dihydroxy-5-(p-(N,N-di(meth)acryloyloxyethylamino)phenylazo)benzophenone,2,4-dihydroxy-3-(o-(N,N-di(meth)acryloyloxyethylamino)phenylazo)benzophenone,2,4-dihydroxy-5-(o-(N,N-di(meth)acryloyloxyethylamino)phenylazo)benzophenone,2,4-dihydroxy-3-(p-(N-ethyl-N-(meth) acryloyloxyethylamino) phenylazo)benzophenone,2,4-dihydroxy-5-(p-(N-ethyl-N-(meth)acryloyloxyethylamino)phenylazo)benzophenone,2,4-dihydroxy-3-(o-(N-ethyl-N-(meth)acryloyloxyethylamino)phenylazo)benzophenone,2,4-dihydroxy-5-(o-(N-ethyl-N-(meth)acryloyloxyethylamino)phenylazo)benzophenone,2,4-dihydroxy-3-(p-(N-ethyl-N-(meth)acryloylamino)phenylazo)benzophenone,2,4-dihydroxy-5-(p-(N-ethyl-N-(meth)acryloylamino)phenylazo)benzophenone,2,4-dihydroxy-3-(o-(N-ethyl-N-(meth)acryloylamino)phenylazo)benzophenoneand2,4-dihydroxy-5-(o-(N-ethyl-N-(meth)acryloylamino)phenylazo)benzophenone;polymerizable benzoic acid type ultraviolet absorbing dyestuff such as2-hydroxy-4-(p-styrenoazo)benzoic acid phenyl, and the like. These canbe used alone or a mixture of 2 or more of compounds can be used.

The contents of the polymerizable ultraviolet absorbent, thepolymerizable dyestuff, and the polymerizable ultraviolet absorbingdyestuff are greatly influenced by the thickness of a lens. The useamount is at most 3 parts based on 100 parts of the total amount ofpolymerization components and preferably 0.01 to 2 parts. When theseamounts exceed 3 parts, the mechanical strength of the ocular lensmaterial and the like tend to be lowered. Further, considering thetoxicity of the ultraviolet absorbent and dyestuff, it tends to be notsuitable as the ocular lens material such as a contact lens whichdirectly contacts with biomedical tissues and an intraocular lens whichis inserted within a living organ. In particular, in case of thedyestuff, when the amount to much, the color of a lens thickens,transparency is lowered, and the lens hardly transmits visible light.Further, when a water content is low in a ocular lens prepared and theelution of the non-polymerizable ultraviolet absorbent, the dyestuff,and the ultraviolet absorbing dyestuff is not confirmed,non-polymerizable components such as2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-(hexyloxy)phenol and2-(5-chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methylphenolcan be also used.

In the ocular lens material of the present invention in which thecompound (A) having bifunctional polymerizable group and the pyrrolidonederivative (B) are main components, the residue of the polymerizablecomponents is very few, and a crosslinking agent is not basicallyrequired. However, a crosslinking agent (G) for adjusting theflexibility and hardness of the material can be added.

Examples of the crosslinking agent (G) used in the present inventioninclude allyl methacrylate, vinyl methacrylate, 4-vinylbenzylmethacrylate, 3-vinylbenzyl methacrylate, methacryloyloxyethyl acrylate,ethyleneglycol dimethacrylate, diethyleneglycol dimethacrylate,diethyleneglycol diallyl ether, triethyleneglycol dimethacrylate,tetraethyleneglycol dimethacrylate, propyleneglycol dimethacrylate,dipropyleneglycol dimethacrylate, butanediol dimethacrylate,trimethylolpropane trimethacrylate,2,2-bis(p-methacryloyloxyphenyl)hexafluoropropane,2,2-bis(m-methacryloyloxyphenyl)hexafluoropropane,2,2-bis(o-methacryloyloxyphenyl)hexafluoropropane,2,2-bis(p-methacryloyloxyphenyl)propane,2,2-bis(m-methacryloyloxyphenyl)propane,2,2-bis(o-methacryloyloxyphenyl)propane,1,4-bis(2-methacryloyloxyhexafluoroisopropyl)benzene,1,3-bis(2-methacryloyloxyhexafluoroisopropyl)benzene,1,2-bis(2-methacryloyloxyhexafluoroisopropyl)benzene,1,4-bis(2-methacryloyloxyisopropyl)benzene,1,3-bis(2-methacryloyloxyisopropyl)benzene,1,2-bis(2-methacryloyloxyisopropyl)benzene, and the like. These can beused alone or a mixture of 2 or more of compounds can be used.

The content of the crosslinking agent (G) is at most one part based on100 parts by weight (hereinafter, referred to as part) of the totalamount of the polymerizable components other than the crosslinking agentand preferably at most 0.8 part so that the ocular lens material is notbrittle. Further, the content is at least 0.05 part based on 100 partsof the total amount of the polymerizable components other than thecrosslinking agent and preferably at least 0.1 part, in order to improvethe mechanical strength of the ocular lens material and adequatelyexpress the effect of imparting durability.

In the ocular lens material of the present invention, when thecrosslinking agent (G) is used, the compound (A) and the crosslinkingagent (G) are simultaneously used as crosslinkable components; thereforethe copolymerizability of the ocular lens material is remarkablyimproved and the various physical properties of the ocular lens materialobtained can be improved.

The stress relaxation coefficient of the ocular lens material of thepresent invention indicates the relaxation coefficient of stress for 30seconds under loading a fixed load and is preferably 8 to 15% and morepreferably 8 to 13%. When it is less than 8%, the material is superiorin stress relaxation but the elongation of the material is not observedand flexibility tends to be lacking. On the other hand, when it exceeds15%, the material is lacking in stress relaxation, the rigidity to keepits shape is inferior, lens movement on eyes tends to be poor and it isoccasionally adhered to the cornea. Consequently, it cannot be said thatthe material has suitable stress relaxation as an ocular lens.

Further, the tensile modulus of the ocular lens material of the presentinvention is preferably 0.2 to 0.8 MPa and more preferably 0.2 to 0.7MPa. When it is less than 0.2 MPa, the material has no body, is inferiorin shape stability on fingers when being used as an ocular lens, and itshandling tends to be difficult. On the other hand, when it exceeds 0.8MPa, the material is hard, deteriorates patient comfort, and tends to bea cause for phisiological responses such as corneal staining andconjunctive staining. Accordingly, it cannot be said that either of themhas flexibility suitable for an ocular lens.

Further, the ocular lens material of the present invention is requiredto be that both of the stress relaxation coefficient and tensile modulusare within a preferable range. A material in which both is not withinthe range generates possibly lens adhesion to cornea or the staining ofcornea and conjunctiva at continuous wearing or at wearing state atshort sleep and the like and it can be said that such material is aninappropriate material as a contact lens. It is necessary forcomfortable wearing that the material has good balance in thefore-mentioned stress relaxation and flexibility.

The percentage of water content of the ocular lens material of thepresent invention is preferably 10 to 60% by weight and more preferably32 to 55% by weight. When the percentage of water content is less than10% by weight, the material is semi hard, and for example, when it isused as a contact lens, the patient comfort tends to be deteriorated. Onthe other hand, when the percentage of water content exceeds 60% byweight, oxygen permeability becomes dependent on the percentage of watercontent and adequate oxygen tends to be not fed to cornea consideringcontinuous wearing or wearing state at short sleep.

The ocular lens material of the present invention can be preparedaccording to the following procedure.

a) A step of obtaining a mixed solution comprising at least one kind ofa compound (A) having ethylenically unsaturated groups andpolydimethylsiloxane structures through a urethane bond, a hydrophilicmonomer (B) comprising at least one kind of a pyrrolidone derivative inwhich a polymerizable group is a methylene group and an photopolymerization initiator and/or a thermal polymerization initiator,

b) a step of introducing said mixed solution to a mold for molding,

c) a step of obtaining an ocular lens material cured by irradiating UVlight on and/or heating the mix solution in said mold for molding,

d) a step of carrying out surface treatment to said ocular lens materialafter demolding said ocular lens material to impart hydrophilicity anddeposit resistance,

e) a step of removeing an unreacted component from said ocular lensmaterial, and

f) a step of hydrating said ocular lens material.

As mentioned above, the fore-mentioned mixed solution comprisespreferably the compound (A), the pyrrolidone derivative (B), thesilicone compound (C) and the N-substituted acrylamide (D) forexpressing the properties of respective polymerizable components.

In the present invention, the fore-mentioned mixed solution comprisespreferably a water-soluble organic solvent for improving the uniformityof components in the polymerizable components. Specifically, anunreacted monomer can be diffused in the system to be participated inpolymerization reaction after proceeding of the polymerization reaction,by presenting a very slight amount of non-polymerizable organic solventon the polymerizable components. Concretely, the residual polymerizablecomponents can be reduced by using a water-soluble organic solvent.

The water-soluble organic solvent used in the present invention is awater-soluble organic solvent selected from alcohols having 1 to 4carbons such as methanol, ethanol, 1-propanol and 2-propanol, oracetone, methylethylketone, dimethylformamide, dimethylsulfoxide,acetonitrile and N-methyl-2-pyrrolidone. As the organic solvent, asolvent capable of dissolving the polymerizable components used may besuitably selected to be used in accordance with the kind of thepolymerizable components. Further, these may be used alone or a mixtureof 2 or more of compounds may be used.

The water-soluble organic solvent in the present invention can dissolvethe polymerizable components of the ocular lens material. Its use amountin the fore-mentioned mixed solution is preferably at most 5% by weight,preferably 0.1 to 5% by weight and further preferably 0.2 to 4% byweight. When the use amount is less than 0.1% by weight, the amount ofthe residual components at polymerization tends to be increased. On theother hand, when it exceeds 5% by weight, the mixed solution of thepolymerizable components in which a diluent is added is heterogeneous,phase separation is generated at polymerization reaction which iscarried out later, and the material obtained tends to become opaque.

Further, since the organic solvent used is soluble in water, it can beeasily replaced with water at a step of elution treatment which iscarried out later.

A bulk polymerization process has been conventionally used inpreparation of the ocular lens material. In the polymerization process,since only the polymerizable components are mixed to be provided forpolymerization, the viscosity of the system is extremely increased inaccordance with proceeding of the polymerization, the components cannotbe diffused in the highly viscous system, and a lot of monomers whichcannot be participated in the polymerization reaction remain. Theelution treatment by water or the organic solvent is carried out forreducing monomers remaining as low as possible.

For obtaining the copolymer composing the ocular lens material of thepresent invention, the contents of the compound (A) and the pyrrolidonederivative (B) as essential components and if necessary, the contents ofthe silicone compound (C), the N-substituted acrylamide (D), thehydrophilic monomer (E), the monomer (F) and the crosslinking agent (G)are adjusted so as to be respectively within the fore-mentioned range,and the polymerizable components are polymerized with heating and/orirradiating ultraviolet rays by means of a molding method.

When the polymerizable components are heated to be polymerized by meansof a molding method, the polymerizable mixture and a radicalpolymerization initiator are pipetted in a mold corresponding to theshape of desired ocular lens, then said mold is gradually heated tocarry out the polymerization of the polymerizable components, andmechanical process such as cutting process and polishing process iscarried out to the molded article obtained if necessary. Further, thecutting may be carried out to the whole area of at least one face orboth faces of the molded article (copolymer), and may be carried out topart of at least one face or both faces. As the ocular lens material ofthe present invention, those which were obtained by cutting at least oneside or part of the molded article (copolymer) are preferable inparticular, considering versatile use of producst such as special lens.The cutting of at least one side of the molded article (copolymer)includes Blanks-molding, namely, a concept that the blanks obtained bypolymerization by means of a molding method is cut to obtain a desiredshape of an ocular lens. Further, the polymerization may be carried out,for example, by a bulk polymerization method and may be carried out by asolution polymerization method using a solvent and the like.

The specific examples of the fore-mentioned radical polymerizationinitiator include, for example, 2,2′-azobisisobutyronitrile,2,2′-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, t-butylhydroperoxide, cumene hydroperoxide, lauroyl peroxide, t-butylperoxyhexanoate, 3,5,5-trimethylhexanoyl peroxide and the like. These can beused alone or a mixture of 2 or more of compounds can be used. Theamount of said radical polymerization initiator is about 0.001 to 2parts based on 100 parts of the polymerizable components and preferably0.01 to 1 part.

The heating temperature at heating the polymerizable components in amold is at least 50° C. and preferably at least 60° C. from theviewpoints of the shortening of polymerization time and the reduction ofthe residual monomer components. Further, it is at most 150° C. andpreferably at most 140° C. from the viewpoints of suppressing theevaporation of the respective polymerizable components and preventingthe deformation of the mold. Further, the heating time at heating thepolymerizable components in a mold is at least 10 minutes and preferablyat least 20 minutes from the viewpoints of the shortening ofpolymerization time and the reduction of the residual monomercomponents. Further, it is at most 120 minutes and preferably at most 60minutes from the viewpoint of preventing the deformation of the mold.Further, the heating may be carried out by stepwise raising temperature.

When ultraviolet rays are irradiated to the polymerizable components tobe polymerized, the polymerizable mixture and a photopolymerizationinitiator are pipetted in a mold corresponding to the shape of desiredocular lens, then ultraviolet rays are irradiated to said mold to carryout the polymerization of the polymerizable components, and mechanicalprocess such as cutting process and polishing process is carried out tothe molded article obtained if necessary. Further, the cutting may becarried out to the whole area of at least one face or both faces of themolded article (copolymer), and may be carried out to part of at leastone face or both faces. As the ocular lens material of the presentinvention, those which were obtained by cutting at least one side orpart of the molded article (copolymer) are preferable in particular,considering versatile use of products such as special lens. The cuttingof at least one side of the molded article (copolymer) includesBlanks-molding, namely, a concept that the blanks obtained bypolymerization by means of a molding method is cut to obtain a desiredshape of an ocular lens. Further, the polymerization may be carried out,for example, by a bulk polymerization method and may be carried out by asolution polymerization method using a solvent and the like. Further, inthe present invention, the polymerization is carried out by thefore-mentioned irradiation of ultraviolet rays, but the irradiation ofelectron beam can be carried out in place of the irradiation ofultraviolet rays. In this case, the polymerizable components can bepolymerized without a photo polymerization initiator.

The quality of a material of the mold used in polymerization by theirradiation of ultraviolet rays is preferably multi-purpose resins suchas a polypropylene, a polystyrene, a nylon and a polyester which cantransmit ultraviolet rays necessary for curing the material, and may beglass. These are molded and processed to prepare desired shapes. Afterthe polymerizable components and the photo polymerization initiator, adyestuff, an ultraviolet-ray absorbent and an organic diluent are mixedand pipetted in a mold which is corresponded to the shape of a lens forthe eyes or not corresponded, and ultraviolet rays are irradiated to themold to carry out the polymerization of the polymerizable components.The wavelength range of UV irradiated can be selected in accordance withthe function of the ocular lens material. However, the kind of the photopolymerization initiator used is required to be selected depending onthe UV wavelength region irradiated.

The preferable irradiance of ultraviolet ray at irradiating ultravioletray to the polymerizable components in the mold is at least 1.0 mW/cm²for adequately curing the material and at most 50 mW/cm² for preventingthe deterioration of the material. The irradiation time is preferably atleast 1 minute for adequately curing the material. The irradiation ofultraviolet rays may be carried out at one step and ultraviolet rayswith different intensity may be irradiated stepwise. Further, heatingmay be simultaneously carried out at irradiation of ultraviolet raysduring polymerization and thereby, the polymerization reaction ispromoted and an ocular lens can be effectively molded.

The fore-mentioned heating temperature is preferably at least 25° C.from the viewpoint of promoting the reaction, more preferably at least30° C. and further preferably at most 100° C. from the viewpoint ofsuppressing the deformation of the mold, more preferably at most 90° C.After polymerization, mechanical process such as cutting process andpolishing process is carried out to the molded article obtained ifnecessary. Further, the cutting may be carried out to the whole area ofat least one face or both faces of the molded article (copolymer), andmay be carried out to part of at least one face or both faces. As theocular lens material of the present invention, those which were obtainedby cutting at least one side or part of the molded article (copolymer)are preferable in particular, considering versatile use of products suchas special lens. The cutting of at least one side or part of the moldedarticle (copolymer) includes namely, a concept that blanks obtained bypolymerization by means of a molding method is cut to obtain a desiredshape of an ocular lens. Further, in the present invention, thepolymerization is carried out by the fore-mentioned irradiation ofultraviolet rays but the irradiation of electron beam can be carried outin place of the irradiation of ultraviolet rays, and in this case, thepolymerizable components can be polymerized without a photopolymerization initiator.

The specific example of the fore-mentioned photo polymerizationinitiator include, for example, phosphine oxide type photopolymerization initiators such as2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) andbis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide; benzoin type photopolymerization initiators such as methyl orthobenzoylbenzoate, methylbenzoylformate, benzoin methyl ether, benzoin ethyl ether, benzoinisopropyl ether, benzoin isobutyl ether and benzoin n-butyl ether;phenone type photo polymerization initiators such as2-hydroxy-2-methyl-1-phenylpropan-1-on,p-isopropyl-α-hydroxyisobutylphenone, p-t-butyl-trichloroacetophenone,2,2-dimethoxy-2-phenylacetophenone, α,α-dichloro-4-phenoxyacetophenoneand N,N-tetraethyl-4,4-diaminobenzophenone; 1-hydroxycyclohexyl phenylketone; 1-phenyl-1,2-propandion-2-(o-ethoxycarbonyl)oxime; thioxanthonetype photo polymerization initiators such as 2-chlorothioxanthone and2-methylthioxanthone; dibenzosvarron; 2-ethylanthraquinone; benzophenoneacrylate; benzophenone; benzyl and the like. These may be used alone ora mixture of 2 or more of these compounds may be used.

Further, a photo sensitizer may be used together with the photopolymerization initiator. The contents of these photo polymerizationinitiator and photo sensitizer is about 0.001 to 2 parts based on 100parts of the polymerizable components and preferably 0.01 to 1 part.

When an intraocular lens is prepared by polymerizing the polymerizablecomponents by heating or by polymerizing them by irradiation ofultraviolet rays or electron beams, the haptic of the lens may beseparately prepared from the lens and then assembled with the lens, ormay be integrally molded together with the lens simultaneously.

The following surface treatments can be carried out for improving thesurface property of an ocular lens. By these surface treatments, thesurface of the ocular lens material further superior in wettabilityand/or deposit resistance can be obtained.

Plasma treatment at low temperature which is known to those skilled inthe art can be carried out under a specific condition under dilute gasatmosphere such as alkane having 1 to 6 carbons and alkane substitutedwith fluorine, nitrogen, oxygen, argon, hydrogen, air, water, silane ora mixture thereof. In particular, oxygen alone, or a mixture of oxygenand water, tetrafuluoromethane, organic silane, methane or nitrogen ispreferable for a reason that the effect of physical surface improvementby ion etching and chemical surface improvement by radical implantation(the introduction of an oxygen atom) are expected.

Hereat, the plasma treatment at low temperature may be under reducedpressure (low pressure) or under atmospheric pressure. The low-pressureplasma treatment or the atmospheric plasma treatment at low temperaturecan control the effect of surface improvement by appropriately adjustinghigh frequency wave RF (for example, 13.56 MHz) and low frequency waveAF (for example, 15.0 to 40.0 kHz), micro wave (for example, 2.45 GHz),output power (optimum value different depending on frequency), treatmenttime (treatment from micro second order to about 1 hour) and gasconcentration (in case of low pressure, the degree of reduced pressureis for example, 10 to 150 Pa).

For example, when oxygen is used, the effect of physical surfaceimprovement by ion etching and chemical surface improvement by radicalimplantation (the introduction of an oxygen atom) are expected. Inaddition, chemical surface improvement can be carried out only byradical implantation. In this case, there can be used a pulse modulationtype device (treatment is repeated while adjusting the time of ON/OFF ofplasma), a remote type device in which a chamber for generating plasmaand a chamber for carrying out treatment are different, or a down flowtype device can be used.

Further, when a mixed gas of methane and air is used, a carbondeposition film containing nitrogen is formed on the surface of asubstrate and when tetramethoxysilane and oxygen are used, a orderly andhardly silicate film is formed on the surface of a substrate. Thereby,highly hydrophilic surface coating superior in durability can be formed.

The surface prepared by these methods is superior in the wettabilityand/or deposit resistance, also superior in the durability of propertiesand can be preferably used as an ocular lens material.

Further, the effective improvement of the wettability and/or depositresistance can be achieved by forming the coating of the hydrophilicpolymer on the surface of the substrate of an ocular lens.

Procedures known to those skilled in the art are applied as a method offorming the coating of the hydrophilic polymer. For example, a method ofsurface improvement by the plasma polymerized coating by carrying outglow discharge (plasma) under atmosphere of the gasified hydrophilicmonomer. In this case, the fragment of a monomer and active species arerandomly re-combined with the substrate, additionally, thepolymerization of the monomer by generated radicals occurs also, therebya polymer coating which was highly and randomly crosslinked can beformed on the surface of the substrate.

The plasma polymerization is carried out, for example, under theconditions below.

Flow rate of plasma gas (argon, nitrogen and the like: 1 to 50 sccm)

Flow rate of monomer gas (1 to 50 sccm)

Glow discharge (frequency; 13.56 MHz, output power; 30 to 100 W,pressure; 1.0 to 30 Pa)

The hydrophilic monomer used here is not specifically limited so far asa compound can be gasified at low pressure and under heating.Particularly, pyrrolidone derivatives such as a1-alkyl-3-methylene-2-pyrrolidone; vinyl lactams such as N-VP,acrylamides such as N,N-dimethylacrylamide (herein after, referred to asDMAA), (math)acrylic acid, hydroxyalkyl (meth)acrylate and the like arementioned.

Further, there can be used a method plasma-induced in which the plasmatreatment is carried out under gas atmosphere such as oxygen, nitrogenand argon to generate radicals on the surface of the substrate, then theocular lens material is immersed in a solution of the hydrophilicmonomer, and the polymer coating is formed by being cured by irradiationof ultraviolet rays or by heating. In this case, the conditions of UVirradiation and heating for forming the polymer coating are notspecifically limited. A condition by which the monomer used can beadequately cured can be selected. For example, it is effective torepeatedly carry out irradiation under UV irradiation conditions ofirradiance of 0.5 to 15 mW/cm² (365 nm) for 1 to 30 minutes, ifnecessary. Further, in case of heating, heating at 40 to 100° C. for 10to 24 hours is effective. Further, the UV irradiation or heatingtreatment may be carried out in a state immersed in the fore-mentionedhydrophilic monomer or in a state of stirring, or after immersing, in astate in which the substrate was taken out or dried.

The hydrophilic monomer used here includes pyrrolidone derivatives suchas 1-alkyl-3-methylene-2-pyrrolidone; vinyl lactams such as N-VP;acrylamides such as DMAA; (meth)acrylic acid, hydroxyalkyl methacrylate;zwitter ion containing compounds such as2-methacrlyloyloxyethylphosphorylcholine (MPC) andN-(3-sulfopropyl)methacrlyloyloxyethyl-N,N-dimethylammonium betaine(SPE); and a mixture thereof. In this case, since the monomer isgraft-polymerized using the radical of the substrate as an initiatingpoint, it is preferable for forming an effective coating with superiordurability that a crosslinking agent exists in mixture in a monomersolution. The crosslinking agent includes ethylene glycol dimethacrylate(EDMA), polyethylene glycol di(meth)acrylate, allyl methacrylate (AMA),diethylene glycol diallyl ether and the like. However, the crosslinkingagent which can be used is not also specifically limited. Thecrosslinking agent can be appropriately selected depending on themonomer used and a solvent. Further, the solvent used is notspecifically limited, and water-soluble solvents such as water,methanol, ethanol, 2-propanol, acetone, acetonitrile and THF arementioned. Among these, water which can be used for hydration treatmentas it is most preferable considering as an ocular lens.

When the molded article (copolymer) obtained is essentially awater-containing material, the desired shape of the ocular lens materialis obtained by immersing the molded article which was formed as anocular lens shape by cutting process or the molded article of the shapeof the ocular lens material which was taken out from a mold, indistilled water or a saline solution, and the polymerizable componentswhich are not reacted, an organic diluent and the like can besimultaneously removed. In order to effectively remove thefore-mentioned compounds capable of being eluted, distilled water or asaline solution may be heated at the same time with hydration of thelens or after hydration. The heating temperature is preferably atemperature at which a residual article can be removed in a short timeand less than the deformation temperature of the ocular lens material,and is preferably, for example, 35 to 100° C.

The colorless and transparent lens after the elution treatment can bealso colored using a vat dye. The vat dyes used are dyes such as anindanthron type, a pyranthrone type, a benzanthorone type, ananthraquinonecarbazole type, an anthraquinoneoxazole type and an indigotype. Preferable examples include C.I.VAT BLUE 4, C.I.VAT BLUE 6 andC.I.VAT BROWN 1 for the indanthron type; C.I.VAT GREEN 1 for thepyranthrone type; C.I.VAT BROWN 2 for the anthraquinonecarbazole type;C.I.VAT BLUE 1 for the indigo type, etc.

The dyeing steps of these vat dyes include steps below.

1) A water-insoluble vat dye is dispersed in water.

2) A dye is reduced to be a water-soluble leuco dye.

3) A leuco dye is adsorbed on a substrate.

4) A dye is oxidized on a substrate and returned to be an originalwater-insoluble dye.

5) A reduction solution and an excessive dye are rinsed and removed.

The reduction condition of the vat dye is important because it greatlyinfluences its dyeing properties. It is usually influenced by theconcentration of alkali, the concentration of a reducing agent, and thetemperature of reduction and dyeing. Further, the solubility of theleuco compound, affinity to a substrate and the like affect also greatlydyeing properties. As the reduction condition, the concentration ofsodium hydroxide is 0.0050 to 5.0 mol/L, the concentration of sodiumhydrosulfite being a reducing agent is 0.001 to 50 g/L, the temperatureof reduction is room temperature to 80° C., and its dyeing temperatureis also preferably room temperature to 80° C. Further, the concentrationof dyeing is preferably 0.0001 to 1.0 g/L. The immersion time iscorrelative to the concentration of dyeing but the shading of the dyeingcan be generally controlled by immersion for 30 seconds to 1 hour.

Further, there is also possible dyeing by a soluble vat dye which wasobtained by preliminarily leuco sulfate esterifying of a water-insolublevat dye. Examples include C.I. solubilised VAT BLUE 6 for thefore-mentioned indanthron type; C.I. solubilised VAT GREEN 1 for thepyranthrone type; C.I. solubilised VAT BLUE 1 for the indigo type andthe like. When the soluble vat dye is used, it can be directly mixed inthe original monomer mixture of the ocular lens material to be used.

Since the ocular lens material of the present invention thus obtained isexcellent in surface wettability and the lubricity/easy lubricatingproperty of surface in addition to high oxygen permeability and highmechanical strength, it can be preferably used for, for example, acontact lens, an intraocular lens, an artificial cornea, cornea onlay,cornea inlay and the like.

Then, the ocular lens material of the present invention is furtherillustrated in detail based on Examples, but the present invention isnot limited to only such Examples.

(Preparation of Macromonomer (A1))

In a 1 L three necked flask equipped with a Dimroth condenser, amechanical stirrer and a thermometer at side tubes which waspreliminarily replaced with nitrogen, 75.48 g (0.34 mol) of isophoronediisocyanate (IPDI) and 0.12 g of iron acetylacetonate (FeAA) was added.Then, 529.90 g of polydimethylsiloxane with hydroxyl groups at bothterminals (KF-6002, manufactured by Shin-Etsu Chemical Co. Ltd.; adegree of polymerization of 40, having a mean molecular weight of 1560g/mol, hereinafter, referred to as DHDMSi40) was added thereto to bestirred for about 4 hours in an oil bath which was heated at 80° C.

Then, 39.47 g (0.34 mol) of 2-hydroxyethyl acrylate (HEA) and 0.20 g ofp-methoxyphenol (MEHQ) as a polymerization inhibitor were added in thethree necked flask to be stirred in an oil bath at 80° C. After about 3hours, the confirmation of the reaction was carried out from thereaction solution using ¹H-NMR and FT/IR and it was confirmed that aprescribed compound was obtained. Further, the crude compound wasextracted and rinsed with n-hexane and acetonitrile, the n-hexane phasewas collected and the organic solvent and low molecular weight compoundswere distilled off to obtain 522.33 g (yield; 81%) of a purifiedcompound.

NMR; (in CDCl₃); δ0.06 ppm(Si—CH₃,m), 0.52(Si—CH₂,2H,m),2.91(NH—CH₂,2H,d), 3.02(CH₂—N═C═O,2H,s), 3.42(—O—CH₂,2H,t),3.61(—O—CH₂,2H,m), 4.18-4.34(—(O)CO—CH₂—,6H,m), 4.54(NH,1H,s),4.85(NH,1H,s), 5.84(CH═,1H,dd), 6.14(CH═,1H,dd), 6.43(CH═,1H,dd)

FT/IR; 1262 and 802 cm⁻¹ (Si—CH₃), 1094 and 1023 cm⁻¹ (Si—O—Si), 1632(C═C) and nearby 1728 cm⁻¹ (C═O, ester and urethane).

(Preparation of Macromonomer (A2))

In a 1 L three necked flask equipped with a Dimroth condenser, amechanical stirrer and a thermometer at side tubes which waspreliminarily replaced with nitrogen, 44.60 g (0.20 mol) of isophoronediisocyanate (IPDI) and 0.07 g of iron acetylacetonate (FeAcAc) wasadded. Then, 90.80 g of dimethylsiloxane with hydroxyl groups at bothterminals (KF-6001, manufactured by Shin-Etsu Chemical Co. Ltd.; adegree of polymerization of 10, having a mean molecular of 1000 g/mol,hereinafter, referred to as DHDMSi10) was added thereto to be stirredfor about 4 hours in an oil bath which was heated at 80° C.

Then, a solution in which 0.07 g of iron acetylacetonate (FeAA) and156.80 g of polyethylene glycol (having a mean molecular weight of 1020g/mol, manufactured by Aldrich Corporation) was dissolved in 200 mL ofchloroform were added thereto to be refluxed for about 4 hours. Theportion of the reaction solution was taken out, the solvent wasdistilled off under reduced pressure, and then the hydroxyl value of theintermediate obtained was measured (acetylation method, 4210 g/mol).

In a 500 mL three necked flask in which 106.50 g of the fore-mentionedintermediate was separately batched off, 7.90 g (0.05 mol) of2-isocyanatoethyl methacrylate (IEM) was added. As a polymerizationinhibitor, 0.05 g of p-methoxyphenol (MEHQ) was added in the threenecked flask to be stirred in an oil bath at 80° C. After about 3 hours,the confirmation of the reaction was carried out from the reactionsolution using ¹H-NMR and FT/IR and it was confirmed that a urethanecompound was obtained. Further, the crude compound was extracted andrinsed with n-hexane and methanol, the n-hexane phase was collected andthe organic solvent and low molecular weight compounds were distilledoff to obtain 84.56 g (yield; 74%) of a purified compound.

NMR; (in CDCl₃); δ 0.06 ppm(Si—CH₃,m), 0.52(Si—CH₂,2H,m),2.91(NH—CH₂,2H,d), 3.02(CH₂—N═C═O,2H,s), nearby 3.5(—O—CH₂,m),4.18-4.34(—(O)CO—CH₂—,6H,m), 4.54(NH,1H,s), 4.85(NH,1H,s),5.84(CH═,1H,dd), 6.14(CH═,1H,dd), 6.43(CH═,1H,dd)

FT/IR; 1262 and 802 cm⁻¹ (Si—CH₃), 1094 and 1023 cm⁻¹ (Si—O—Si), 1632(C═C) and nearby 1728 cm⁻¹ (C═O, ester and urethane).

Abbreviations below are used in Examples.

TRIS: Tris(trimethylsiloxy)silylpropyl methacrylate

DMAA: N,N-dimethylacrylamide

1,3-MMP: 1-Methyl-3-methylene-2-pyrrolidone

1,5-MMP: 1-Methyl-5-methylene-2-pyrrolidone

5,3-MMP: 5-Methyl-3-methylene-2-pyrrolidone

NiPMP: 1-i-Propyl-3-methylene-2-pyrrolidone

N-VP: N-vinyl-2-pyrrolidone

MMA: Methyl methacrylate

EDMA: Ethylene glycol dimethacrylate

NMP: 1-Methyl-2-pyrrolidone

TPO: 2,4,6-Trimethylbenzoyl-diphenylphosphine oxide

HMPPO: 2-Hydroxy-2-methyl-propiophenone

BAPO: Bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide

ADMVN: 2,2′-Azobis(2,4-dimethylvaleronitrile)

CBDMP:2-(5-Chloro-2H-benzotriazol-2-yl)-6-(1,1-dimethylethyl)-4-methylphenol

HPT: 2-(4,6-Diphenyl-1,3,5-triazin-2-yl)-5-(hexyloxy)phenol

BZT-MA:2-(2′-Hydroxy-5′-(2″-methacryloyloxyethoxy)-3′-t-butylphenyl)-5-methyl-2H-benzotriazole

APMA: Tetra-(4-methacrylamide)copper phthalocyanine

PAMNp: 1-Phenylazo-3-methacryloyloxy-2-naphthole

Further, the amounts (parts in weight) of a crosslinking agent, apolymerization initiator, an ultraviolet absorbent, a colorant and adiluent in Table are amounts based on 100 parts of the polymerizablecomponents other than these.

The determination of residual monomers in the contact lens polymerobtained in Examples, the determination of eluted articles in aprocessing solution after hydration treatment, the transparency of thecontact lens, the lubricity of surface, wettability, a contact angle,stress relaxation, a tensile modulus, oxygen permeability, a refractiveindex, a water content and lipid deposition were studied according tomethods below.

(Determination of Residual Monomers (HPLC))

After polymerization, a lens taken out from a mold was immersed inacetonitrile and the extraction of residual components was carried out.The extract was analyzed with HPLC, and the residual rates of monomersbased on mixed amounts were calculated with respect to 1,3-MMP, 1,5-MMP,5,3-MMP and N-VP whose residual amounts are comparatively much. At thedetermination of the residual rates, the acetonitrile solutions of1,3-MMP, 1,5-MMP, 5,3-MMP and N-VP were prepared and analyzed with HPLC.According to the analytical results, the concentrations (ppm) ofrespective monomers were set as an X-axis and the analytical values ofrespective peak areas were set as a Y-axis to prepare calibrationcurves. The residual rates S1 (%) for the amount of a pyrrolidonemonomer used and the residual rates S2 (%) for the total amount of alens are shown as follow using V: the amount of an extraction solvent(mL), A: the peak area of a monomer, a; the gradient of a calibrationcurve, b: the intercept of a calibration curve, W: the weight (g) of aplate and w: the weight proportion (%) of an objective monomer atmixing.S1 (%)={V×(A−b)}/(a×W×w×100)S2 (%)={V×(A−b)/(a×W×10000)(TOC Analysis)

Lens materials of Example 1 and Comparative Example 1 just afterpolymerization were used as samples. After the weight of these sampleswere measured, the sample was charged one by one in a vial container inwhich 20 mL of ultra pure water was charged and autoclave was carriedout at 121° C. for 10 minutes. 5 Samples were prepared per the samematerial, lenses were taken out just after cooling (0 day), the firstday, the third day, 8^(th) day and 14^(th) day after autoclaving, andthe analysis of the processing solutions was carried out by TOC. Themeasurement was carried out using a total organic carbon meter (TOC)(TOC-V_(CSH)) manufactured by Shimadzu Corporation and carried out withNPOC (Non Purgeable Organic Carbon) mode. The results are shown in Table4. The determination values (ppmC) in the table show the concentrationsof an extract when the concentration just after (0 day) the autoclavetreatment was referred to as zero. Namely, a large value indicates thatthe elution amount is much.

(Transparency)

The appearance of a contact lens is visually observed and evaluatedbased on the following criteria.

Evaluation Criteria

A: Clouding is not observed at all, transparency is extremely superiorand it is most suitable as a contact lens.

B: Clouding is slightly observed and it has transparency which is out ofproblem as a contact lens.

C: Since opaque is confirmed and transparency is inferior, it isdifficult to be used as a contact lens.

D: Since opaque is confirmed and transparency is extremely inferior, itis impossible to be used as a contact lens.

(Surface Lubricity and Wettability)

A contact lens was folded into two and rubbed between fingers to examinelubricity (adhesion state of the lens with itself and adhesion state ofthe lens and the finger). Further, the wettability of lens surface wasvisually confirmed.

Evaluation Criteria

A: The wettability is good, the lubricity of mutual lenses is good andit is most suitable as a contact lens.

B: The wettability is slightly deficient and when mutual lenses arerubbed, creak is slightly felt.

C: There is no adhesiveness of a lens with fingers but the slip ofmutual lenses is bad and movement is not occasionally observed.

D: Stickiness is observed on lens surface and the adhesion feeling of alens with fingers is strong.

(Contact Angle (Bubble Method))

A contact angle (°) (a bubble method) was measured in a saline solutionat a temperature of 25° C. using a contact anglemeter G-I, 2MGmanufactured by Erma Sales Co., LTD. 10 μL of bubbles were applied tothe film immersed in the saline solution by using a syringe, and thecontact angles between the foams and the left and right of a plate wereaveraged to be referred to as the value of a contact angle. The smallerthe value of a contact angle is, the better the wettability is.

(Stress Relaxation)

The periphery of an ocular lens material is fixed and its center wasfixed on a loading device with a 1/16 inch ball pointed jig. A load ofabout 20 g was added on the ocular lens material and stopped, stress (So(g/mm²)) was measured just after the stoppage, it was further left alonefor 30 seconds, then its stress (S (g/mm²)) was measured. The stressrelaxation (%) was calculated in accordance with following equationusing So and S measured.

Further, when the Stress relaxation (%)={(So−S)/So}×100 is at least 15%,the ocular lens material is lacking in stress relaxation and inferior inthe rigidity to keep its lens shape and it cannot be said that it hasflexibility suitable as the ocular lens material.Stress relaxation (%)={(So−S)/So}×100(Tensile Modulus)

Sample having a dumbbell shape of a stretched portion with a width of 2mm and a thickness of 0.3 mm were punched out and tensile tests werecarried out by using an INSTRON universal material tester Mode 14300.The measurement was carried out in a saline solution at 35° C. andYoung's modulus was calculated from a stress-elongation curve. Further,when the Young's modulus is larger than 0.8 MPa, the elasticity of theocular lens material is high and there is high possibility to cause thefixation of a lens at wearing the lens and affections such as corneastaining.

(Oxygen Permeability Coefficient Dk)

The oxygen permeability coefficients of test pieces were measured in asaline solution at 35° C. by using Seikaken-type film oxygen-gaspermeator manufactured by RIKASEIKI KOGYO Co., LTD. The measurement ofeither of test pieces with a thickness of 0.1 to 0.4 mm was carried outin accordance with ISO 9913-1 using a cigarette paper. Calculationconsidering edge effect was carried out and the Dk value wasstandardized as 64 using MENICON EX (manufactured by Menicon Co.) as areference standard. Further, the unit of the oxygen permeabilitycoefficient is (×10⁻¹¹ (cm²/sec)) (mLO₂/mL×hPa) and this is a valueobtained by multiplying the unit (×10⁻¹¹ (cm²/sec)) (mLO₂/mL×mmHg) whichhas been conventionally used in the skilled in the art, by 0.75.

(Refractive Index)

Refractive index (no unit) was measured at a temperature of 25° C. underatmosphere with a humidity of 50% using an ATAGO Refractometer 1Tmanufactured by ATAGO CO., LTD.

(Water Content)

After hydration treatment was carried out to a test piece, the watercontent of the test piece was measured in accordance with the followingequation. Provided that W represents the weight (g) of the test piece inequilibrated swollen state after the hydration treatment and W₀represents the weight (g) of the test piece in state in which it wasdried at 105° C. in a dryer for 16 hours after the hydration treatment.Water content (% by weight)=(W−W ₀)×100/W(Lipid Deposition Test)

After a lens was immersed at 37° C. for 5 hours in an artificial tearlipid solution consisting of oleic acid, tripalmitic acid, palmiticacid, cholesterol, cholesterol palmitate and yolk lecithin, it wasextracted with ethanol and diethyl ether, and an lipid deposition(mg/cm²) was determined by a SPV method.

EXAMPLES 1 TO 3 AND COMPARATIVE EXAMPLE 1

Ocular Lens components mixed with the polymerizable components andpolymerization initiator shown in Table 1 were injected into a mold(made of a polypropylene; corresponding to a contact lens with adiameter of about 13 mm and a thickness of 0.1 mm) having a contact lensshape. Then, photo polymerization was carried out by irradiating UVlight on the mold for 60 minutes to obtain polymers having a contactlens shape. The results evaluating the amounts of unreacted residualmonomers in the polymer were shown in Tables 2 and 3 and the evaluationresults of the concentration of eluted articles in the processingsolution by TOC after hydration were shown in Table 4. TABLE 1 Monomermixing ratio (parts by weight) Ex. Com. Ex. 1 2 3 1 TRIS 27 27 27 27Macromonomer A1 23 23 23 23 DMAA 10 10 10 10 N-VP — — — 40 1,3-MMP 40 —— — 1,5-MMP — 40 — — 5,3-MMP — — 40 — EDMA 0.4 0.4 0.4 0.4 HMPPO 0.4 0.40.4 0.4

TABLE 2 Monomer residual rate (based on monomer) Ex. Com. Ex. Residualrate S1 (%) 1 2 3 1 N-VP — — — 2.6 1,3-MMP 0.5 — — — 1,5-MMP — 0.9 — —5,3-MMP — — 0.4 —

TABLE 3 Monomer residual rate (based on total weight) Ex. Com. Ex.Residual rate S2(%) 1 2 3 1 N-VP — — — 1.0 1,3-MMP 0.2 — — — 1,5-MMP —0.3 — — 5,3-MMP — — 0.1 —

TABLE 4 TOC aging change Quantity value (ppm) 1st day 3rd day 8th day14th day Ex. 1(1,3-MMP) 0.9 2.2 1.9 4.8 Com. Ex. 1(N-VP) 5.9 5.9 8.911.8

EXAMPLES 4 TO 31 AND COMPARATIVE EXAMPLES 2 TO 5

Ocular Lens components mixed with the polymerizable components,polymerization initiator, UV absorbent, Dye and a diluent shown inTables 5 to 9 were injected into a mold (made of a polypropylene) havinga contact lens shape. Then, photopolymerization was carried out byirradiating UV light on the mold for 30 minutes to obtain polymershaving a contact lens shape. Plasma irradiation (an RF output power of50 W and a pressure of 100 Pa) under oxygen atmosphere was carried outon the polymers obtained, for 3 minutes. They were immersed in a salinesolution and hydration treatment was carried out by absorbing water toobtain contact lenses. The evaluation results were shown in Tables 10 to14. TABLE 5 Monomer mixing ratio (parts by weight) Ex. 4 5 6 7 8 9 10TRIS 30 30 30 30 27.5 22 22 Macromonomer A1 30 30 30 30 27.5 33 33 DMAA10 10 10 10 11.3 11.3 11.3 N-VP — — — — — — — 1,3-MMP 30 30 — — 33.733.7 33.7 1,5-MMP — — 30 — — — — 5,3-MMP — — — 30 — — — EDMA 0.4 0.4 0.40.4 0.4 0.4 0.4 HMPPO 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Dye APMA None APMAAPMA APMA PAMNp None 0.01 0.01 0.01 0.01 0.01

TABLE 6 Monomer mixing ratio (parts by weight) Ex. 11 12 13 14 15 16 17TRIS 22 22 30 30 30 30 25 Macromonomer A1 33 33 20 20 20 20 25 DMAA 11.311.3 12.5 12.5 12.5 12.5 12.5 N-VP — — — — — — — 1,3-MMP — — 37.5 37.5 —— 37.5 1,5-MMP 33.7 — — — 37.5 — — 5,3-MMP — 33.7 — — — 37.5 — EDMA 0.40.4 0.4 0.4 0.4 0.4 0.4 HMPPO 0.4 0.4 0.4 0.4 0.4 0.4 0.4 Dye PAMNpPAMNp APMA None APMA APMA APMA 0.01 0.01 0.01 0.01 0.01 0.01

TABLE 7 Monomer mixing ratio (parts by weight) Com. Ex. 2 3 4 5 TRIS 2537.5 50 40 Macromonomer A1 25 12.5 — — DMAA 12.5 10 12.5 12.5 N-VP 37.540 — — 1,3-MMP — — 37.5 37.5 1,5-MMP — — — — 5,3-MMP — — — — MMA — 10EDMA 0.4 0.4 0.4 0.4 HMPPO 0.4 0.4 0.4 0.4 Dye (APMA) 0.01 0.01 0.010.01

TABLE 8 Monomer mixing ratio (parts by weight) Ex. 18 19 20 21 22 23 2425 TRS 30 27.5 22 22 30 25 30 25 Macromonomer A1 A1 A1 A1 A1 A1 A2 A2 3027.5 33 33 20 20 30 25 DMAA 10 11.3 11.3 11.3 12.5 13.8 10 12.5 N-VP — —— — — — — — 1,3-MMP 30 33.7 33.7 33.7 37.5 41.2 30 37.5 EDMA 0.4 0.4 0.40.4 0.4 0.4 0.4 0.4 Photopolymerization TPO TPO HMPPO HMPPO BAPO BAPOHMPPO HMPPO initiator 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 UV absorbent CBDMPHPT BZT-MA BZT-MA CBDMP HPT None None 0.2 0.2 0.5 0.5 0.2 0.2 APMA 0.010.01 None 0.01 0.01 0.01 0.01 0.01

TABLE 9 Monomer mixing ratio (parts by weight) Ex. 26 27 28 29 30 31TRIS 30 25 30 22 22 30 Macromonomer 30 25 30 33 33 30 A1 DMAA 10 12.5 1011.3 11.3 10 1,3-MMP — — 30 — — — 1,5-MMP — — — 33.7 — — 5,3-MMP — — — —33.7 — NiPMP 30 37.5 — — — 30 EDMA 0.4 0.4 0.4 0.4 0.4 0.4 HMPPO 0.4 0.40.4 0.4 0.4 0.4 APMA 0.01 0.01 0.01 0.01 0.01 0.01 Diluent — — NMPEthanol Ethanol Ethanol 2.5 2.5 2.5 2.5

TABLE 10 Evaluation results of physical and chemical properties Ex. 4 56 7 8 9 10 Transparency A A A A A A A Surface lubricity and B B B B A AA wettability Contact angle (°) 28 29 29 26 27 26 26 Stress relaxation(%) 13 13 13 13 13 12 12 Tensile modulus 0.28 0.30 0.28 0.32 0.25 0.390.37 (MPa) Dk 78 88 88 92 69 90 90 Water content (%) 34 34 30 35 40 4040 Refractive index 1.426 1.426 1.433 1.424 1.420 1.420 1.420 Residualrate S1 (%) 1.4 — — — 1.5 0.4 0.5 MMP

TABLE 11 Evaluation results of physical and chemical properties Ex. 1112 13 14 15 16 17 Transparency A A A A A A A Surface lubricity and A A AA A A A wettability Contact angle (°) 26 25 27 27 28 26 22 Stressrelaxation (%) 12 13 10 10 11 12 13 Tensile modulus 0.36 0.40 0.37 0.400.36 0.40 0.23 (MPa) Dk 79 83 66 78 74 75 53 Water content (%) 35 43 4545 42 47 47 Refractive index 1.424 1.419 1.421 1.421 1.421 1.414 1.412Residual rate S1 (%) 0.9 0.4 2.1 1.9 2.2 1.2 2.3 MMP

TABLE 12 Evaluation results of physical and chemical properties Com. Ex.2 3 4 5 Transparency A A C B Surface lubricity and A A B B wettabilityContact angle (°) 22 23 28 27 Stress relaxation (%) 10 16 Incapable 37measurement* Tensile modulus 0.47 0.22 Incapable 0.56 (MPa) measurement*Dk 79 50 Incapable 31 measurement* Water content (%) 45 54 60 54Refractive index 1.414 1.400 Incapable 1.404 measurement* Residual rateS1 (%) 4.0 4.0 — — M-VP*Incapable measurement: Because of lack in the rigidity to keep its lensshape (deformation) and poor mechanical strength.

TABLE 13 Evaluation results of physical and chemical properties Ex. 1819 20 21 22 23 24 25 Transparency A A A A A A A A Surface lubricity A BA A A A A A and wettability Contact angle (°) 27 27 26 26 28 25 26 22Stress relaxation 13 12 13 13 12 12 13 13 (%) Tensile modulus 0.29 0.460.43 0.38 0.31 0.30 0.26 0.23 (MPa) Dk 74 71 87 86 66 58 70 51 Watercontent 34 33 39 40 40 51 36 48 (%) Refractive index 1.426 1.427 1.4201.420 1.420 1.407 1.424 1.412 Residual rate S1 1.5 1.8 0.9 1.1 2.4 2.82.3 2.5 (%) MMP

TABLE 14 Evaluation results of physical and chemical properties Ex. 2627 28 29 30 31 Transparency A A A A A A Surface A B A A A A lubricityand wettability Contact 28 28 26 28 28 25 angle (°) Stress 13 13 12 1213 12 relaxation (%) Tensile 0.31 0.27 0.28 0.36 0.40 0.26 modulus (MPa)Dk 74 52 76 75 80 74 Water 32 41 35 35 42 32 content (%) Refractive1.428 1.420 1.425 1.424 1.420 1.428 index Residual rate 1.6 2.4 0.5 0.70.2 0.8 S1 (%) MMP

EXAMPLES 32 AND 33

After plasma irradiation (an output power of 50 W and a pressure of 100Pa, for 3 minutes) under oxygen atmosphere was carried out for polymersbefore hydration which were obtained by using the similar mixedsolutions as Examples 1 and 11, they were immersed in an aqueoussolution (5.0% by weight of diethylene glycol diallyl ether wascontained) of 5.0% by mol of N-VP and graft polymer films were formed byheating at 60° C. for 30 minutes. Hydration treatment was carried out toobtain contact lenses. The evaluation results were shown in Table 15.

EXAMPLES 34 AND 35

After plasma irradiation (an output power of 50 W and a pressure of 100Pa, for 3 minutes) under oxygen atmosphere was carried out for polymersbefore hydration which were obtained by using the similar mixedsolutions as Examples 1 and 11, they were immersed in an aqueoussolution (5.0% by weight of tetraethylene glycol dimethacrylate wascontained) of 1.0% by mol of MPC (2-methacrylolyloxyethylphosphorylcholine) and graft polymer films were formed by UV irradiation for 10minutes. Hydration treatment was carried out to obtain contact lenses.The evaluation results were shown in Table 15.

EXAMPLES 36 AND 37

Glow discharge (a pressure of 13 Pa and an RF output power of 40 W, for5 minutes×twice) under tetramethoxysilane (TMS)/oxygen (a gas flow ratioof 1/2 sccm) atmosphere was carried out for polymers before hydrationwhich were obtained by using the similar mixed solutions as Examples 1and 11, and plasma polymerized films were formed. Hydration treatmentwas carried out to obtain contact lenses. The evaluation results wereshown in Table 15.

EXAMPLES 38 AND 39

Glow discharge (a pressure of 4 Pa and an AF output power of 40 W, for 5minutes×twice) under methane (CH4)/air (a gas flow ratio of 3/2 sccm)atmosphere was carried out for polymers before hydration which wereobtained by using the similar mixed solutions as Examples 1 and 11, andcarbon deposited films were formed. Further, usual oxygen plasma andhydration treatment were carried out to obtain contact lenses. Theevaluation results were shown in Table 15. TABLE 15 Evaluation resultsof physical and chemical properties Ex. 32 33 34 35 36 37 38 39 MaterialExample 1 11 1 11 1 11 1 11 Surface treatment PVP PVP PMPC PMPC SilicateSilicate Carbon Carbon graft graft graft graft coating coating DepositedDeposited film film Transparency A A A A A A A A Feeling test A A A A AA A A Contact angle (°) 20 22 21 24 20 21 28 30 Lipid deposition 0.070.10 0.08 0.10 0.10 0.11 0.10 0.12 (mg/cm²)

EXAMPLES 40 AND 41

Glow discharge (a pressure of 13 Pa and an RF output power of 300 W, for5 minutes) under tetrafluoromethane (CF4)/oxygen (a gas flow ratio of9/1) atmosphere was carried out for polymers before hydration which wereobtained by using the similar mixed solutions as Examples 1 and 11.Hydration treatment was carried out to obtain contact lenses. Theevaluation results were shown in Table 16.

EXAMPLE 42

After plasma irradiation (an output power of 50 W and a pressure of 100Pa, for 3 minutes) under oxygen atmosphere was carried out for a polymerbefore hydration which was obtained by using the similar mixed solutionas Example 1, hydration treatment was carried out to obtain contactlenses. The evaluation results were shown in Table 16.

EXAMPLE 43

After plasma irradiation (an output power of 2.5 KW and a pressure of133 Pa, for 3 minutes) under oxygen/water (a gas flow ratio of 9/1)atmosphere was carried out for a polymer before hydration which wasobtained by using the similar mixed solution as Example 11, hydrationtreatment was carried out to obtain contact lenses. The evaluationresults were shown in Table 16.

EXAMPLE 44

Hydration treatment was carried out for a polymer before hydration whichwas obtained by using the similar mixed solution as Example 1, to obtaincontact lenses. The evaluation results were shown in Table 16. TABLE 16Evaluation results of physical and chemical properties Ex. 40 41 42 4344 Material Example 1 11 1 11 1 Surface treatment CF₄ CF₄ O₂ O₂ + H₂OUntreated etching etching plasma (90/10) Transparency A A A A A Surfacelubricity A A A A B and wettability Contact angle (°) 25 26 28 28 36Lipid deposition 0.14 0.15 0.21 0.24 0.44 (mg/cm²)Preparation of Colored Lens by Vat Dyes

EXAMPLES 45 TO 50

Colored lenses were obtained by the method below using vat dye for thecontact lenses which were obtained by the similar procedure as Examples1, 11 and 21.

After the contact lenses after hydration treatment were immersed in areduction solution consisting of 0.1 g of sodium hydroxide, 0.1 g ofsodium hydrosulfite and 19.8 g of purified water, about 2.0 g of adyeing solution in which 300 ppm of each of various vat dyes shown inTable 17 was dissolved in a mixed solution with the same composition asthe reduction solution was mixed with the reduction solution in whichthe contact lenses were preliminarily immersed, stirred for 15 minutesand adequately rinsed to obtain the contact lenses. The evaluationresults were shown in Table 17. TABLE 17 Coloring by Vat dye Ex. 45 4647 48 49 50 Lens 1 1 11 11 21 21 Example Vat blue 1 Bluish-purple, — — —— — no deformation Vat blue 6 — — Blue, — Blue, — no deformation nodeformation Vat brown 1 — Pale brown, — — — — no deformation Vat green 1— — — Blue green, — Blue green, no deformation no deformation

EXAMPLES 51 TO 55

Ocular Lens components mixed with the polymerizable components,polymerization initiator, UV absorbent, Dye and diluent shown in Table18 were injected into a mold (made of a polypropylene) having a contactlens shape. Then, the mold was heated in an oven adjusted at 100±2° C.for 30 minutes to obtain polymers having a contact lens shape. Plasmairradiation (an RF output power of 50 W and a pressure of 100 Pa) underoxygen atmosphere was carried out for the polymers obtained, for 3minutes. They were immersed in a saline solution and hydration treatmentwas carried out by absorbing water to obtain contact lenses. Theevaluation results were shown in Table 19. TABLE 18 Monomer mixing ratio(parts by weight) Ex. 51 52 53 54 55 TRIS 30 22 22 30 25 Macro monomerA1 30 33 33 20 20 DMAA 10 11.3 11.3 16.7 13.8 N-VP — — — — — 1,3-MMP 3033.7 33.7 33.3 41.2 EDMA 0.4 0.4 None None None Polymerization initiator0.4 0.4 0.4 0.4 0.4 (ADMVN) UV absorbent 0.3 0.3 0.3 0.3 0.3 (BZT-MA)APMA 0.01 0.01 0.01 0.01 0.01

TABLE 19 Evaluation results of physical and chemical properties Ex. 5152 53 54 55 Transparency A A A A A Surface lubricity and A A A A Awettability Contact angle (°) 28 26 26 26 25 Stress relaxation (%) 13 1311 12 12 Tensile modulus (MPa) 0.32 0.44 0.30 0.32 0.29 Dk 77 67 67 6760 Water content (%) 34 41 41 41 52 Refractive index 1.426 1.420 1.4201.420 1.408 Residual rate S1 (%) 0.4 0.6 0.7 0.6 0.7 1,3-MMPClinical Evaluation

Contact lenses described in Examples 4, 8, 17, 32 and 34 imparted goodcomfort at wearing and there were no slitlamp findings. On the otherhand, although there was no slitlamp findings in wearing of contactlenses described in Comparative Example 2, it was uncomfortable.Further, in the wearing test of the contact lenses described inComparative Example 3 which were low in repulsive property, the lensmovement was poor and slow and adhesion on the cornea was confirmed.

From the above results, the contact lens materials shown in Examples 1to 55 are excellent in transparency and low frictional property,additionally, excellent in surface wettability, excellent in flexibilityand repulsive property because stress relaxation is 13% or less, furtherlow in the residual rate of monomers, and high in safety because anelution amount to a lens preservating solution is small. Additionally,they impart also good comfort at wearing the contact lenses; thereforeit is grasped that they are preferable as contact lenses.

Further, since the residual rate of the pyrrolidone derivative in lensesafter polymerization is low in the material using the fore-mentionedpyrrolidone derivative and the silicone-containing macromonomer, it canbe achieved to shorten the production step of an ocular lens.

On the other hand, although the materials of Comparative Examples whichare not included within the claims are superior in transparency, lowfrictional property, flexibility and surface wettability, the residualrate of monomers is large, elution to an autoclave processing solutionis also confirmed and further, adsorption is confirmed at wearinglenses; therefore they are not preferable as an ocular lens material.

INDUSTRIAL APPLICABILITY

According to the present invention, a contact lens excellent intransparency, oxygen permeability, flexibility, stress relaxation,surface wettability and lubricity, little in surface sticking property,and having appropriate mechanical property, additionally, the lowresidual rate of monomers, low elution amount to an autoclave processingsolution, high safety and good patient comfort is obtained.

Further, since the ocular lens material comprising the pyrrolidonederivatives in which the polymerizable group is a methylene group andspecific silicone-containing macromonomer is excellent inpolymerizability, it can be used as a highly safe ocular lens materialused as an intraocular lens, an artificial cornea, or a cornea onlay anda cornea inlay which is buried in the body.

Consequently, the present invention provides not only a contact lens butalso an ocular lens material having versatile uses.

Further, since the residual rate in the lens after polymerization of thepyrrolidone derivatives in which the polymerizable group is a methylenegroup is low in a contact lens which uses the pyrrolidone derivatives inwhich the polymerizable group is a methylene group and specificsilicone-containing macromonomer, the present invention can achieve thesimplification of the preparation process.

1. An ocular lens material comprising at least one kind of a compound(A) having an ethylenically unsaturated group and polydimethylsiloxanestructure through a urethane bond and at least one kind of a pyrrolidonederivative (B) in which a polymerizable group is a methylene group. 2.An ocular lens material according to claim 1, comprising 5 to 60% byweight of the pyrrolidone derivatives in which the polymerizable groupis a methylene group.
 3. An ocular lens material according to claim 1 or2, wherein the pyrrolidone derivatives in which the polymerizable groupis a methylene group is 1-alkyl-3-methylene-2-pyrrolidone.
 4. An ocularlens material according to claim 3, wherein the1-alkyl-3-methylene-2-pyrrolidone (B) is1-methyl-3-methylene-2-pyrrolidone.
 5. An ocular lens material accordingto claim 1 or 2, wherein at least one of the pyrrolidone derivatives inwhich the polymerizable group is a methylene group is1-alkyl-5-methylene-2-pyrrolidone.
 6. An ocular lens material accordingto claim 5, wherein the 1-alkyl-5-methylene-2-pyrrolidone (B) is1-methyl-5-methylene-2-pyrrolidone.
 7. An ocular lens material accordingto claim 1 or 2, wherein at least one of the pyrrolidone derivatives inwhich the polymerizable group is a methylene group is5-alkyl-3-methylene-2-pyrrolidone.
 8. An ocular lens material accordingto claim 7, wherein the 5-alkyl-3-methylene-2-pyrrolidone (B) is5-methyl-3-methylene-2-pyrrolidone.
 9. An ocular lens material accordingto claim 1, wherein the repeating number of siloxane of thepolydimethylsiloxane structure in a compound (A) having ethylenicallyunsaturated groups and polydimethylsiloxane structure through a urethanebond is 10 to
 100. 10. An ocular lens material according to claim 1,wherein tensile modulus is 0.2 to 0.8 MPa and stress relaxation underloading a fixed load for 30 seconds is 8 to 15%.
 11. An ocular lensmaterial according to claim 1, wherein water content is 10 to 60% byweight.
 12. An ocular lens material according to claim 1, wherein watercontent is 32 to 55% by weight.
 13. An ocular lens material according toclaim 1, wherein (C) a silicone compound other than the compound (A)having ethylenically unsaturated groups and polydimethylsiloxanestructure through a urethane bond is contained.
 14. An ocular lensmaterial according to claim 13, wherein the silicone compound (C) istris(trimethylsiloxy)silylpropyl (meth)acrylate.
 15. An ocular lensmaterial according to claim 1 or 13, wherein a N-substituted acrylamide(D) is further comprised.
 16. An ocular lens material according to claim15, wherein the N-substituted acrylamide (D) is at least one ofN-substituted acrylamides selected from the group consisting ofN,N-dimethyl acrylamide, N,N-diethyl acrylamide, acryloyl morpholine,N-isopropyl acrylamide and N-(2-hydroxyethyl) acrylamide.
 17. An ocularlens material according to claim 1 or 13, wherein at least one of acrosslinking agent is further comprised.
 18. A lens for the eyescomprising the ocular lens material according to claim
 1. 19. A methodfor preparing an ocular lens material, comprising a) a step of obtaininga mixed solution comprising at least one kind of a compound (A) havingethylenically unsaturated groups and polydimethylsiloxane structuresthrough a urethane bond and a hydrophilic monomer (B) comprising atleast one kind of a pyrrolidone derivative in which a polymerizablegroup is a methylene group and an photo polymerization initiator and/ora thermal polymerization initiator, b) a step of introducing said mixedsolution to a mold, c) a step of obtaining an ocular lens material curedby irradiating UV light on and/or heating the mixed solution in saidmold, d) a step of carrying out surface treatment to said ocular lensmaterial after demolding said ocular lens material to imparthydrophilicity and deposit resistance, e) a step of removing anunreacted component from said ocular lens material, and f) a step ofhydrating said ocular lens material.
 20. A method for preparing theocular lens material according to claim 19, comprising at least one ofthe compounds (A) having ethylenically unsaturated groups andpolydimethylsiloxane structures through a urethane bond, at least one ofthe pyrrolidone derivatives (B) in which the polymerizable group is amethylene group, the silicone compound (C) and the N-substitutedacrylamide (D) in the mixed solution.
 21. A method for preparing theocular lens material according to claim 19 or 20, containing acrosslinking agent in the mixed solution.
 22. A method for preparing theocular lens material according to claim 19 or 20, containing at leastone of polymerizable or non polymerizable ultraviolet absorbents and/orat least one of polymerizable or non polymerizable dyes in the mixedsolution.
 23. A method for preparing the ocular lens material accordingto claim 19 or 20, comprising 0.1 to 5% by weight of a water-solubleorganic solvent.
 24. A method for preparing the ocular lens materialaccording to claim 23, wherein the water-soluble organic solvent is awater-soluble organic solvent selected from alcohols having 1 to 4carbons, acetone, methyl ethyl ketone, dimethylformamide,dimethylsulfoxide, acetonitrile and N-methyl-2-pyrrolidone.
 25. A methodfor preparing the ocular lens material according to claim 19, whereinthe surface treatment is plasma treatment.
 26. A method for preparingthe ocular lens material according to claim 25, wherein oxygen or amixture of oxygen is used in the plasma treatment.
 27. A method forpreparing the ocular lens material according to claim 26, wherein amixture of oxygen and water is used in the plasma treatment.
 28. Amethod for preparing the ocular lens material according to claim 26,wherein a mixture of oxygen and tetrafluoromethane is used in the plasmatreatment.
 29. A method for preparing the ocular lens material accordingto claim 26, wherein a mixture of oxygen and organic silane is used inthe plasma treatment.
 30. A method for preparing the ocular lensmaterial according to claim 29, wherein the organic silane istetramethoxysilane.
 31. A method for preparing the ocular lens materialaccording to claim 26, wherein a mixture of oxygen and methane is usedin the plasma treatment.
 32. A method for preparing the ocular lensmaterial according to claim 26, wherein a mixture of oxygen, nitrogenand methane is used in the plasma treatment.
 33. A method for preparingthe ocular lens material according to claim 19, wherein the surfacetreatment is a treatment according to the coating method of ahydrophilic polymer coating.
 34. A method for preparing the ocular lensmaterial according to claim 33, wherein the coating method is a plasmapolymerization method of a hydrophilic monomer.
 35. A method forpreparing the ocular lens material according to claim 33, wherein thecoating method is a plasma-induced graft polymerization.
 36. A methodfor preparing the ocular lens material according to claim 19, furthercomprising (g) a step of coloring the ocular lens material by using avat dye.